New upstream version 0.99.0

148 files changed, 7119 insertions, 2882 deletions

diff --git a/.circleci/config.yml b/.circleci/config.yml
index 697e6c57..ee72ad7a 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -4,8 +4,8 @@ jobs:
     machine: true
     steps:
       - checkout
-      - run: docker build -f docker/Dockerfile --label gitsha1=${CIRCLE_SHA1} -t matrixdotorg/synapse:${CIRCLE_TAG} .
-      - run: docker build -f docker/Dockerfile --label gitsha1=${CIRCLE_SHA1} -t matrixdotorg/synapse:${CIRCLE_TAG}-py3 --build-arg PYTHON_VERSION=3.6 .
+      - run: docker build -f docker/Dockerfile --label gitsha1=${CIRCLE_SHA1} -t matrixdotorg/synapse:${CIRCLE_TAG}-py2 .
+      - run: docker build -f docker/Dockerfile --label gitsha1=${CIRCLE_SHA1} -t matrixdotorg/synapse:${CIRCLE_TAG} -t matrixdotorg/synapse:${CIRCLE_TAG}-py3 --build-arg PYTHON_VERSION=3.6 .
       - run: docker login --username $DOCKER_HUB_USERNAME --password $DOCKER_HUB_PASSWORD
       - run: docker push matrixdotorg/synapse:${CIRCLE_TAG}
       - run: docker push matrixdotorg/synapse:${CIRCLE_TAG}-py3
@@ -13,8 +13,8 @@ jobs:
     machine: true
     steps:
       - checkout
-      - run: docker build -f docker/Dockerfile --label gitsha1=${CIRCLE_SHA1} -t matrixdotorg/synapse:latest .
-      - run: docker build -f docker/Dockerfile --label gitsha1=${CIRCLE_SHA1} -t matrixdotorg/synapse:latest-py3 --build-arg PYTHON_VERSION=3.6 .
+      - run: docker build -f docker/Dockerfile --label gitsha1=${CIRCLE_SHA1} -t matrixdotorg/synapse:latest-py2 .
+      - run: docker build -f docker/Dockerfile --label gitsha1=${CIRCLE_SHA1} -t matrixdotorg/synapse:latest -t matrixdotorg/synapse:latest-py3 --build-arg PYTHON_VERSION=3.6 .
       - run: docker login --username $DOCKER_HUB_USERNAME --password $DOCKER_HUB_PASSWORD
       - run: docker push matrixdotorg/synapse:latest
       - run: docker push matrixdotorg/synapse:latest-py3
diff --git a/.codecov.yml b/.codecov.yml
new file mode 100644
index 00000000..a05698a3
--- /dev/null
+++ b/.codecov.yml
@@ -0,0 +1,15 @@
+comment:
+  layout: "diff"
+
+coverage:
+  status:
+    project:
+      default:
+        target: 0  # Target % coverage, can be auto. Turned off for now
+        threshold: null
+        base: auto
+    patch:
+      default:
+        target: 0
+        threshold: null
+        base: auto
diff --git a/.coveragerc b/.coveragerc
index 9873a307..e9460a34 100644
--- a/.coveragerc
+++ b/.coveragerc
@@ -1,11 +1,7 @@
 [run]
 branch = True
 parallel = True
-source = synapse
-
-[paths]
-source=
-   coverage
+include = synapse/*
 
 [report]
 precision = 2
diff --git a/.gitignore b/.gitignore
index d739595c..37f0028d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -12,6 +12,7 @@ dbs/
 dist/
 docs/build/
 *.egg-info
+pip-wheel-metadata/
 
 cmdclient_config.json
 homeserver*.db
@@ -25,9 +26,9 @@ homeserver*.pid
 *.tls.dh
 *.tls.key
 
-.coverage
-.coverage.*
-!.coverage.rc
+.coverage*
+coverage.*
+!.coveragerc
 htmlcov
 
 demo/*/*.db
diff --git a/.travis.yml b/.travis.yml
index 84d5efff..3cab77ce 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -12,6 +12,9 @@ cache:
     #
     - $HOME/.cache/pip/wheels
 
+addons:
+  postgresql: "9.4"
+
 # don't clone the whole repo history, one commit will do
 git:
   depth: 1
@@ -68,6 +71,13 @@ matrix:
 
 install:
   - pip install tox
+  
+  # if we don't have python3.6 in this environment, travis unhelpfully gives us
+  # a `python3.6` on our path which does nothing but spit out a warning. Tox
+  # tries to run it (even if we're not running a py36 env), so the build logs
+  # then have warnings which look like errors. To reduce the noise, remove the
+  # non-functional python3.6.
+  - ( ! command -v python3.6 || python3.6 --version ) &>/dev/null || rm -f $(command -v python3.6)
 
 script:
   - tox -e $TOX_ENV
diff --git a/CHANGES.md b/CHANGES.md
index 6fdd31da..e330aea9 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,79 @@
+Synapse 0.99.0 (2019-02-05)
+===========================
+
+Synapse v0.99.x is a precursor to the upcoming Synapse v1.0 release. It contains foundational changes to room architecture and the federation security model necessary to support the upcoming r0 release of the Server to Server API.
+
+Features
+--------
+
+- Synapse's cipher string has been updated to require ECDH key exchange. Configuring and generating dh_params is no longer required, and they will be ignored. ([\#4229](https://github.com/matrix-org/synapse/issues/4229))
+- Synapse can now automatically provision TLS certificates via ACME (the protocol used by CAs like Let's Encrypt). ([\#4384](https://github.com/matrix-org/synapse/issues/4384), [\#4492](https://github.com/matrix-org/synapse/issues/4492), [\#4525](https://github.com/matrix-org/synapse/issues/4525), [\#4572](https://github.com/matrix-org/synapse/issues/4572), [\#4564](https://github.com/matrix-org/synapse/issues/4564), [\#4566](https://github.com/matrix-org/synapse/issues/4566), [\#4547](https://github.com/matrix-org/synapse/issues/4547), [\#4557](https://github.com/matrix-org/synapse/issues/4557))
+- Implement MSC1708 (.well-known routing for server-server federation) ([\#4408](https://github.com/matrix-org/synapse/issues/4408), [\#4409](https://github.com/matrix-org/synapse/issues/4409), [\#4426](https://github.com/matrix-org/synapse/issues/4426), [\#4427](https://github.com/matrix-org/synapse/issues/4427), [\#4428](https://github.com/matrix-org/synapse/issues/4428), [\#4464](https://github.com/matrix-org/synapse/issues/4464), [\#4468](https://github.com/matrix-org/synapse/issues/4468), [\#4487](https://github.com/matrix-org/synapse/issues/4487), [\#4488](https://github.com/matrix-org/synapse/issues/4488), [\#4489](https://github.com/matrix-org/synapse/issues/4489), [\#4497](https://github.com/matrix-org/synapse/issues/4497), [\#4511](https://github.com/matrix-org/synapse/issues/4511), [\#4516](https://github.com/matrix-org/synapse/issues/4516), [\#4520](https://github.com/matrix-org/synapse/issues/4520), [\#4521](https://github.com/matrix-org/synapse/issues/4521), [\#4539](https://github.com/matrix-org/synapse/issues/4539), [\#4542](https://github.com/matrix-org/synapse/issues/4542), [\#4544](https://github.com/matrix-org/synapse/issues/4544))
+- Search now includes results from predecessor rooms after a room upgrade. ([\#4415](https://github.com/matrix-org/synapse/issues/4415))
+- Config option to disable requesting MSISDN on registration. ([\#4423](https://github.com/matrix-org/synapse/issues/4423))
+- Add a metric for tracking event stream position of the user directory. ([\#4445](https://github.com/matrix-org/synapse/issues/4445))
+- Support exposing server capabilities in CS API (MSC1753, MSC1804) ([\#4472](https://github.com/matrix-org/synapse/issues/4472), [81b7e7eed](https://github.com/matrix-org/synapse/commit/81b7e7eed323f55d6550e7a270a9dc2c4c7b0fe0)))
+- Add support for room version 3 ([\#4483](https://github.com/matrix-org/synapse/issues/4483), [\#4499](https://github.com/matrix-org/synapse/issues/4499), [\#4515](https://github.com/matrix-org/synapse/issues/4515), [\#4523](https://github.com/matrix-org/synapse/issues/4523), [\#4535](https://github.com/matrix-org/synapse/issues/4535))
+- Synapse will now reload TLS certificates from disk upon SIGHUP. ([\#4495](https://github.com/matrix-org/synapse/issues/4495), [\#4524](https://github.com/matrix-org/synapse/issues/4524))
+- The matrixdotorg/synapse Docker images now use Python 3 by default. ([\#4558](https://github.com/matrix-org/synapse/issues/4558))
+
+Bugfixes
+--------
+
+- Prevent users with access tokens predating the introduction of device IDs from creating spurious entries in the user_ips table. ([\#4369](https://github.com/matrix-org/synapse/issues/4369))
+- Fix typo in ALL_USER_TYPES definition to ensure type is a tuple ([\#4392](https://github.com/matrix-org/synapse/issues/4392))
+- Fix high CPU usage due to remote devicelist updates ([\#4397](https://github.com/matrix-org/synapse/issues/4397))
+- Fix potential bug where creating or joining a room could fail ([\#4404](https://github.com/matrix-org/synapse/issues/4404))
+- Fix bug when rejecting remote invites ([\#4405](https://github.com/matrix-org/synapse/issues/4405), [\#4527](https://github.com/matrix-org/synapse/issues/4527))
+- Fix incorrect logcontexts after a Deferred was cancelled ([\#4407](https://github.com/matrix-org/synapse/issues/4407))
+- Ensure encrypted room state is persisted across room upgrades. ([\#4411](https://github.com/matrix-org/synapse/issues/4411))
+- Copy over whether a room is a direct message and any associated room tags on room upgrade. ([\#4412](https://github.com/matrix-org/synapse/issues/4412))
+- Fix None guard in calling config.server.is_threepid_reserved ([\#4435](https://github.com/matrix-org/synapse/issues/4435))
+- Don't send IP addresses as SNI ([\#4452](https://github.com/matrix-org/synapse/issues/4452))
+- Fix UnboundLocalError in post_urlencoded_get_json ([\#4460](https://github.com/matrix-org/synapse/issues/4460))
+- Add a timeout to filtered room directory queries. ([\#4461](https://github.com/matrix-org/synapse/issues/4461))
+- Workaround for login error when using both LDAP and internal authentication. ([\#4486](https://github.com/matrix-org/synapse/issues/4486))
+- Fix a bug where setting a relative consent directory path would cause a crash. ([\#4512](https://github.com/matrix-org/synapse/issues/4512))
+
+
+Deprecations and Removals
+-------------------------
+
+- Synapse no longer generates self-signed TLS certificates when generating a configuration file. ([\#4509](https://github.com/matrix-org/synapse/issues/4509))
+
+
+Improved Documentation
+----------------------
+
+- Update debian installation instructions ([\#4526](https://github.com/matrix-org/synapse/issues/4526))
+
+
+Internal Changes
+----------------
+
+- Synapse will now take advantage of native UPSERT functionality in PostgreSQL 9.5+ and SQLite 3.24+. ([\#4306](https://github.com/matrix-org/synapse/issues/4306), [\#4459](https://github.com/matrix-org/synapse/issues/4459), [\#4466](https://github.com/matrix-org/synapse/issues/4466), [\#4471](https://github.com/matrix-org/synapse/issues/4471), [\#4477](https://github.com/matrix-org/synapse/issues/4477), [\#4505](https://github.com/matrix-org/synapse/issues/4505))
+- Update README to use the new virtualenv everywhere ([\#4342](https://github.com/matrix-org/synapse/issues/4342))
+- Add better logging for unexpected errors while sending transactions ([\#4368](https://github.com/matrix-org/synapse/issues/4368))
+- Apply a unique index to the user_ips table, preventing duplicates. ([\#4370](https://github.com/matrix-org/synapse/issues/4370), [\#4432](https://github.com/matrix-org/synapse/issues/4432), [\#4434](https://github.com/matrix-org/synapse/issues/4434))
+- Silence travis-ci build warnings by removing non-functional python3.6 ([\#4377](https://github.com/matrix-org/synapse/issues/4377))
+- Fix a comment in the generated config file ([\#4387](https://github.com/matrix-org/synapse/issues/4387))
+- Add ground work for implementing future federation API versions ([\#4390](https://github.com/matrix-org/synapse/issues/4390))
+- Update dependencies on msgpack and pymacaroons to use the up-to-date packages. ([\#4399](https://github.com/matrix-org/synapse/issues/4399))
+- Tweak codecov settings to make them less loud. ([\#4400](https://github.com/matrix-org/synapse/issues/4400))
+- Implement server support for MSC1794 - Federation v2 Invite API ([\#4402](https://github.com/matrix-org/synapse/issues/4402))
+- debian package: symlink to explicit python version ([\#4433](https://github.com/matrix-org/synapse/issues/4433))
+- Add infrastructure to support different event formats ([\#4437](https://github.com/matrix-org/synapse/issues/4437), [\#4447](https://github.com/matrix-org/synapse/issues/4447), [\#4448](https://github.com/matrix-org/synapse/issues/4448), [\#4470](https://github.com/matrix-org/synapse/issues/4470), [\#4481](https://github.com/matrix-org/synapse/issues/4481), [\#4482](https://github.com/matrix-org/synapse/issues/4482), [\#4493](https://github.com/matrix-org/synapse/issues/4493), [\#4494](https://github.com/matrix-org/synapse/issues/4494), [\#4496](https://github.com/matrix-org/synapse/issues/4496), [\#4510](https://github.com/matrix-org/synapse/issues/4510), [\#4514](https://github.com/matrix-org/synapse/issues/4514))
+- Generate the debian config during build ([\#4444](https://github.com/matrix-org/synapse/issues/4444))
+- Clarify documentation for the `public_baseurl` config param ([\#4458](https://github.com/matrix-org/synapse/issues/4458), [\#4498](https://github.com/matrix-org/synapse/issues/4498))
+- Fix quoting for allowed_local_3pids example config ([\#4476](https://github.com/matrix-org/synapse/issues/4476))
+- Remove deprecated --process-dependency-links option from UPGRADE.rst ([\#4485](https://github.com/matrix-org/synapse/issues/4485))
+- Make it possible to set the log level for tests via an environment variable ([\#4506](https://github.com/matrix-org/synapse/issues/4506))
+- Reduce the log level of linearizer lock acquirement to DEBUG. ([\#4507](https://github.com/matrix-org/synapse/issues/4507))
+- Fix code to comply with linting in PyFlakes 3.7.1. ([\#4519](https://github.com/matrix-org/synapse/issues/4519))
+- Add some debug for membership syncing issues ([\#4538](https://github.com/matrix-org/synapse/issues/4538))
+- Docker: only copy what we need to the build image ([\#4562](https://github.com/matrix-org/synapse/issues/4562))
+
+
 Synapse 0.34.1.1 (2019-01-11)
 =============================
 
diff --git a/INSTALL.md b/INSTALL.md
new file mode 100644
index 00000000..cbe4bda1
--- /dev/null
+++ b/INSTALL.md
@@ -0,0 +1,410 @@
+* [Installing Synapse](#installing-synapse)
+  * [Installing from source](#installing-from-source)
+    * [Platform-Specific Instructions](#platform-specific-instructions)
+    * [Troubleshooting Installation](#troubleshooting-installation)
+  * [Prebuilt packages](#prebuilt-packages)
+* [Setting up Synapse](#setting-up-synapse)
+  * [TLS certificates](#tls-certificates)
+  * [Registering a user](#registering-a-user)
+  * [Setting up a TURN server](#setting-up-a-turn-server)
+  * [URL previews](#url-previews)
+
+# Installing Synapse
+
+## Installing from source
+
+(Prebuilt packages are available for some platforms - see [Prebuilt packages](#prebuilt-packages).)
+
+System requirements:
+
+- POSIX-compliant system (tested on Linux & OS X)
+- Python 3.5, 3.6, 3.7, or 2.7
+- At least 1GB of free RAM if you want to join large public rooms like #matrix:matrix.org
+
+Synapse is written in Python but some of the libraries it uses are written in
+C. So before we can install Synapse itself we need a working C compiler and the
+header files for Python C extensions. See [Platform-Specific
+Instructions](#platform-specific-instructions) for information on installing
+these on various platforms.
+
+To install the Synapse homeserver run:
+
+```
+mkdir -p ~/synapse
+virtualenv -p python3 ~/synapse/env
+source ~/synapse/env/bin/activate
+pip install --upgrade pip
+pip install --upgrade setuptools
+pip install matrix-synapse[all]
+```
+
+This will download Synapse from [PyPI](https://pypi.org/project/matrix-synapse)
+and install it, along with the python libraries it uses, into a virtual environment
+under `~/synapse/env`.  Feel free to pick a different directory if you
+prefer.
+
+This Synapse installation can then be later upgraded by using pip again with the
+update flag:
+
+```
+source ~/synapse/env/bin/activate
+pip install -U matrix-synapse[all]
+```
+
+Before you can start Synapse, you will need to generate a configuration
+file. To do this, run (in your virtualenv, as before)::
+
+```
+cd ~/synapse
+python -m synapse.app.homeserver \
+    --server-name my.domain.name \
+    --config-path homeserver.yaml \
+    --generate-config \
+    --report-stats=[yes|no]
+```
+
+... substituting an appropriate value for `--server-name`. The server name
+determines the "domain" part of user-ids for users on your server: these will
+all be of the format `@user:my.domain.name`. It also determines how other
+matrix servers will reach yours for Federation. For a test configuration,
+set this to the hostname of your server. For a more production-ready setup, you
+will probably want to specify your domain (`example.com`) rather than a
+matrix-specific hostname here (in the same way that your email address is
+probably `user@example.com` rather than `user@email.example.com`) - but
+doing so may require more advanced setup. - see [Setting up Federation](README.rst#setting-up-federation). Beware that the server name cannot be changed later.
+
+This command will generate you a config file that you can then customise, but it will
+also generate a set of keys for you. These keys will allow your Home Server to
+identify itself to other Home Servers, so don't lose or delete them. It would be
+wise to back them up somewhere safe. (If, for whatever reason, you do need to
+change your Home Server's keys, you may find that other Home Servers have the
+old key cached. If you update the signing key, you should change the name of the
+key in the `<server name>.signing.key` file (the second word) to something
+different. See the
+[spec](https://matrix.org/docs/spec/server_server/latest.html#retrieving-server-keys)
+for more information on key management.)
+
+You will need to give Synapse a TLS certficate before it will start - see [TLS
+certificates](#tls-certificates).
+
+To actually run your new homeserver, pick a working directory for Synapse to
+run (e.g. `~/synapse`), and::
+
+    cd ~/synapse
+    source env/bin/activate
+    synctl start
+
+### Platform-Specific Instructions
+
+#### Debian/Ubuntu/Raspbian
+
+Installing prerequisites on Ubuntu or Debian:
+
+```
+sudo apt-get install build-essential python3-dev libffi-dev \
+                     python-pip python-setuptools sqlite3 \
+                     libssl-dev python-virtualenv libjpeg-dev libxslt1-dev
+```
+
+#### ArchLinux
+
+Installing prerequisites on ArchLinux:
+
+```
+sudo pacman -S base-devel python python-pip \
+               python-setuptools python-virtualenv sqlite3
+```
+
+#### CentOS/Fedora
+
+Installing prerequisites on CentOS 7 or Fedora 25:
+
+```
+sudo yum install libtiff-devel libjpeg-devel libzip-devel freetype-devel \
+                 lcms2-devel libwebp-devel tcl-devel tk-devel redhat-rpm-config \
+                 python-virtualenv libffi-devel openssl-devel
+sudo yum groupinstall "Development Tools"
+```
+
+#### Mac OS X
+
+Installing prerequisites on Mac OS X:
+
+```
+xcode-select --install
+sudo easy_install pip
+sudo pip install virtualenv
+brew install pkg-config libffi
+```
+
+#### OpenSUSE
+
+Installing prerequisites on openSUSE:
+
+```
+sudo zypper in -t pattern devel_basis
+sudo zypper in python-pip python-setuptools sqlite3 python-virtualenv \
+               python-devel libffi-devel libopenssl-devel libjpeg62-devel
+```
+
+#### OpenBSD
+
+Installing prerequisites on OpenBSD:
+
+```
+doas pkg_add python libffi py-pip py-setuptools sqlite3 py-virtualenv \
+              libxslt jpeg
+```
+
+There is currently no port for OpenBSD. Additionally, OpenBSD's security
+settings require a slightly more difficult installation process.
+
+XXX: I suspect this is out of date.
+
+1. Create a new directory in `/usr/local` called `_synapse`. Also, create a
+   new user called `_synapse` and set that directory as the new user's home.
+   This is required because, by default, OpenBSD only allows binaries which need
+   write and execute permissions on the same memory space to be run from
+   `/usr/local`.
+2. `su` to the new `_synapse` user and change to their home directory.
+3. Create a new virtualenv: `virtualenv -p python2.7 ~/.synapse`
+4. Source the virtualenv configuration located at
+   `/usr/local/_synapse/.synapse/bin/activate`. This is done in `ksh` by
+   using the `.` command, rather than `bash`'s `source`.
+5. Optionally, use `pip` to install `lxml`, which Synapse needs to parse
+   webpages for their titles.
+6. Use `pip` to install this repository: `pip install matrix-synapse`
+7. Optionally, change `_synapse`'s shell to `/bin/false` to reduce the
+   chance of a compromised Synapse server being used to take over your box.
+
+After this, you may proceed with the rest of the install directions.
+
+#### Windows
+
+If you wish to run or develop Synapse on Windows, the Windows Subsystem For
+Linux provides a Linux environment on Windows 10 which is capable of using the
+Debian, Fedora, or source installation methods. More information about WSL can
+be found at https://docs.microsoft.com/en-us/windows/wsl/install-win10 for
+Windows 10 and https://docs.microsoft.com/en-us/windows/wsl/install-on-server
+for Windows Server.
+
+### Troubleshooting Installation
+
+XXX a bunch of this is no longer relevant.
+
+Synapse requires pip 8 or later, so if your OS provides too old a version you
+may need to manually upgrade it::
+
+    sudo pip install --upgrade pip
+
+Installing may fail with `Could not find any downloads that satisfy the requirement pymacaroons-pynacl (from matrix-synapse==0.12.0)`.
+You can fix this by manually upgrading pip and virtualenv::
+
+    sudo pip install --upgrade virtualenv
+
+You can next rerun `virtualenv -p python3 synapse` to update the virtual env.
+
+Installing may fail during installing virtualenv with `InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning.`
+You can fix this  by manually installing ndg-httpsclient::
+
+    pip install --upgrade ndg-httpsclient
+
+Installing may fail with `mock requires setuptools>=17.1. Aborting installation`.
+You can fix this by upgrading setuptools::
+
+    pip install --upgrade setuptools
+
+If pip crashes mid-installation for reason (e.g. lost terminal), pip may
+refuse to run until you remove the temporary installation directory it
+created. To reset the installation::
+
+    rm -rf /tmp/pip_install_matrix
+
+pip seems to leak *lots* of memory during installation.  For instance, a Linux
+host with 512MB of RAM may run out of memory whilst installing Twisted.  If this
+happens, you will have to individually install the dependencies which are
+failing, e.g.::
+
+    pip install twisted
+
+## Prebuilt packages
+
+As an alternative to installing from source, prebuilt packages are available
+for a number of platforms.
+
+### Docker images and Ansible playbooks
+
+There is an offical synapse image available at
+https://hub.docker.com/r/matrixdotorg/synapse which can be used with
+the docker-compose file available at [contrib/docker](contrib/docker). Further information on
+this including configuration options is available in the README on
+hub.docker.com.
+
+Alternatively, Andreas Peters (previously Silvio Fricke) has contributed a
+Dockerfile to automate a synapse server in a single Docker image, at
+https://hub.docker.com/r/avhost/docker-matrix/tags/
+
+Slavi Pantaleev has created an Ansible playbook,
+which installs the offical Docker image of Matrix Synapse
+along with many other Matrix-related services (Postgres database, riot-web, coturn, mxisd, SSL support, etc.).
+For more details, see
+https://github.com/spantaleev/matrix-docker-ansible-deploy
+
+
+### Debian/Ubuntu
+
+#### Matrix.org packages
+
+Matrix.org provides Debian/Ubuntu packages of the latest stable version of
+Synapse via https://matrix.org/packages/debian/. To use them:
+
+```
+sudo apt install -y lsb-release curl apt-transport-https
+echo "deb https://matrix.org/packages/debian `lsb_release -cs` main" |
+    sudo tee /etc/apt/sources.list.d/matrix-org.list
+curl "https://matrix.org/packages/debian/repo-key.asc" |
+    sudo apt-key add -
+sudo apt update
+sudo apt install matrix-synapse-py3
+```
+
+#### Downstream Debian/Ubuntu packages
+
+For `buster` and `sid`, Synapse is available in the Debian repositories and
+it should be possible to install it with simply:
+
+```
+    sudo apt install matrix-synapse
+```
+
+There is also a version of `matrix-synapse` in `stretch-backports`. Please see
+the [Debian documentation on
+backports](https://backports.debian.org/Instructions/) for information on how
+to use them.
+
+We do not recommend using the packages in downstream Ubuntu at this time, as
+they are old and suffer from known security vulnerabilities.
+
+### Fedora
+
+Synapse is in the Fedora repositories as `matrix-synapse`:
+
+```
+sudo dnf install matrix-synapse
+```
+
+Oleg Girko provides Fedora RPMs at
+https://obs.infoserver.lv/project/monitor/matrix-synapse
+
+### OpenSUSE
+
+Synapse is in the OpenSUSE repositories as `matrix-synapse`:
+
+```
+sudo zypper install matrix-synapse
+```
+
+### SUSE Linux Enterprise Server
+
+Unofficial package are built for SLES 15 in the openSUSE:Backports:SLE-15 repository at
+https://download.opensuse.org/repositories/openSUSE:/Backports:/SLE-15/standard/
+
+### ArchLinux
+
+The quickest way to get up and running with ArchLinux is probably with the community package
+https://www.archlinux.org/packages/community/any/matrix-synapse/, which should pull in most of
+the necessary dependencies.
+
+pip may be outdated (6.0.7-1 and needs to be upgraded to 6.0.8-1 ):
+
+```
+sudo pip install --upgrade pip
+```
+
+If you encounter an error with lib bcrypt causing an Wrong ELF Class:
+ELFCLASS32 (x64 Systems), you may need to reinstall py-bcrypt to correctly
+compile it under the right architecture. (This should not be needed if
+installing under virtualenv):
+
+```
+sudo pip uninstall py-bcrypt
+sudo pip install py-bcrypt
+```
+
+### FreeBSD
+
+Synapse can be installed via FreeBSD Ports or Packages contributed by Brendan Molloy from:
+
+ - Ports: `cd /usr/ports/net-im/py-matrix-synapse && make install clean`
+ - Packages: `pkg install py27-matrix-synapse`
+
+
+### NixOS
+
+Robin Lambertz has packaged Synapse for NixOS at:
+https://github.com/NixOS/nixpkgs/blob/master/nixos/modules/services/misc/matrix-synapse.nix
+
+# Setting up Synapse
+
+Once you have installed synapse as above, you will need to configure it.
+
+## TLS certificates
+
+The default configuration exposes two HTTP ports: 8008 and 8448. Port 8008 is
+configured without TLS; it should be behind a reverse proxy for TLS/SSL
+termination on port 443 which in turn should be used for clients. Port 8448
+is configured to use TLS for Federation with a self-signed or verified
+certificate, but please be aware that a valid certificate will be required in
+Synapse v1.0. Instructions for having Synapse automatically provision and renew federation certificates through ACME can be found at [ACME.md](docs/ACME.md).
+
+If you would like to use your own certificates, you can do so by changing
+`tls_certificate_path` and `tls_private_key_path` in `homeserver.yaml`;
+alternatively, you can use a reverse-proxy. Apart from port 8448 using TLS,
+both ports are the same in the default configuration.
+
+## Registering a user
+
+You will need at least one user on your server in order to use a Matrix
+client. Users can be registered either via a Matrix client, or via a
+commandline script.
+
+To get started, it is easiest to use the command line to register new
+users. This can be done as follows:
+
+```
+$ source ~/synapse/env/bin/activate
+$ synctl start # if not already running
+$ register_new_matrix_user -c homeserver.yaml https://localhost:8448
+New user localpart: erikj
+Password:
+Confirm password:
+Make admin [no]:
+Success!
+```
+
+This process uses a setting `registration_shared_secret` in
+`homeserver.yaml`, which is shared between Synapse itself and the
+`register_new_matrix_user` script. It doesn't matter what it is (a random
+value is generated by `--generate-config`), but it should be kept secret, as
+anyone with knowledge of it can register users on your server even if
+`enable_registration` is `false`.
+
+## Setting up a TURN server
+
+For reliable VoIP calls to be routed via this homeserver, you MUST configure
+a TURN server.  See [docs/turn-howto.rst](docs/turn-howto.rst) for details.
+
+## URL previews
+
+Synapse includes support for previewing URLs, which is disabled by default.  To
+turn it on you must enable the `url_preview_enabled: True` config parameter
+and explicitly specify the IP ranges that Synapse is not allowed to spider for
+previewing in the `url_preview_ip_range_blacklist` configuration parameter.
+This is critical from a security perspective to stop arbitrary Matrix users
+spidering 'internal' URLs on your network.  At the very least we recommend that
+your loopback and RFC1918 IP addresses are blacklisted.
+
+This also requires the optional lxml and netaddr python dependencies to be
+installed.  This in turn requires the libxml2 library to be available - on
+Debian/Ubuntu this means `apt-get install libxml2-dev`, or equivalent for
+your OS.
diff --git a/MANIFEST.in b/MANIFEST.in
index 29303cc8..eb2de60f 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -15,6 +15,7 @@ recursive-include docs *
 recursive-include scripts *
 recursive-include scripts-dev *
 recursive-include synapse *.pyi
+recursive-include tests *.pem
 recursive-include tests *.py
 
 recursive-include synapse/res *
@@ -37,6 +38,7 @@ prune docker
 prune .circleci
 prune .coveragerc
 prune debian
+prune .codecov.yml
 
 exclude jenkins*
 recursive-exclude jenkins *.sh
diff --git a/README.rst b/README.rst
index 4901e046..e666b3b4 100644
--- a/README.rst
+++ b/README.rst
@@ -81,194 +81,8 @@ Thanks for using Matrix!
 Synapse Installation
 ====================
 
-Synapse is the reference Python/Twisted Matrix homeserver implementation.
+For details on how to install synapse, see `<INSTALL.md>`_.
 
-System requirements:
-
-- POSIX-compliant system (tested on Linux & OS X)
-- Python 3.5, 3.6, 3.7, or 2.7
-- At least 1GB of free RAM if you want to join large public rooms like #matrix:matrix.org
-
-Installing from source
-----------------------
-
-(Prebuilt packages are available for some platforms - see `Platform-Specific
-Instructions`_.)
-
-Synapse is written in Python but some of the libraries it uses are written in
-C. So before we can install Synapse itself we need a working C compiler and the
-header files for Python C extensions.
-
-Installing prerequisites on Ubuntu or Debian::
-
-    sudo apt-get install build-essential python3-dev libffi-dev \
-                         python-pip python-setuptools sqlite3 \
-                         libssl-dev python-virtualenv libjpeg-dev libxslt1-dev
-
-Installing prerequisites on ArchLinux::
-
-    sudo pacman -S base-devel python python-pip \
-                   python-setuptools python-virtualenv sqlite3
-
-Installing prerequisites on CentOS 7 or Fedora 25::
-
-    sudo yum install libtiff-devel libjpeg-devel libzip-devel freetype-devel \
-                     lcms2-devel libwebp-devel tcl-devel tk-devel redhat-rpm-config \
-                     python-virtualenv libffi-devel openssl-devel
-    sudo yum groupinstall "Development Tools"
-
-Installing prerequisites on Mac OS X::
-
-    xcode-select --install
-    sudo easy_install pip
-    sudo pip install virtualenv
-    brew install pkg-config libffi
-
-Installing prerequisites on Raspbian::
-
-    sudo apt-get install build-essential python3-dev libffi-dev \
-                         python-pip python-setuptools sqlite3 \
-                         libssl-dev python-virtualenv libjpeg-dev
-
-Installing prerequisites on openSUSE::
-
-    sudo zypper in -t pattern devel_basis
-    sudo zypper in python-pip python-setuptools sqlite3 python-virtualenv \
-                   python-devel libffi-devel libopenssl-devel libjpeg62-devel
-
-Installing prerequisites on OpenBSD::
-
-    doas pkg_add python libffi py-pip py-setuptools sqlite3 py-virtualenv \
-                 libxslt jpeg
-
-To install the Synapse homeserver run::
-
-    mkdir -p ~/synapse
-    virtualenv -p python3 ~/synapse/env
-    source ~/synapse/env/bin/activate
-    pip install --upgrade pip
-    pip install --upgrade setuptools
-    pip install matrix-synapse[all]
-
-This installs Synapse, along with the libraries it uses, into a virtual
-environment under ``~/synapse/env``.  Feel free to pick a different directory
-if you prefer.
-
-This Synapse installation can then be later upgraded by using pip again with the
-update flag::
-
-    source ~/synapse/env/bin/activate
-    pip install -U matrix-synapse[all]
-
-In case of problems, please see the _`Troubleshooting` section below.
-
-There is an offical synapse image available at
-https://hub.docker.com/r/matrixdotorg/synapse/tags/ which can be used with
-the docker-compose file available at `contrib/docker <contrib/docker>`_. Further information on
-this including configuration options is available in the README on
-hub.docker.com.
-
-Alternatively, Andreas Peters (previously Silvio Fricke) has contributed a
-Dockerfile to automate a synapse server in a single Docker image, at
-https://hub.docker.com/r/avhost/docker-matrix/tags/
-
-Slavi Pantaleev has created an Ansible playbook,
-which installs the offical Docker image of Matrix Synapse
-along with many other Matrix-related services (Postgres database, riot-web, coturn, mxisd, SSL support, etc.).
-For more details, see
-https://github.com/spantaleev/matrix-docker-ansible-deploy
-
-Configuring Synapse
--------------------
-
-Before you can start Synapse, you will need to generate a configuration
-file. To do this, run (in your virtualenv, as before)::
-
-    cd ~/.synapse
-    python -m synapse.app.homeserver \
-        --server-name my.domain.name \
-        --config-path homeserver.yaml \
-        --generate-config \
-        --report-stats=[yes|no]
-
-... substituting an appropriate value for ``--server-name``. The server name
-determines the "domain" part of user-ids for users on your server: these will
-all be of the format ``@user:my.domain.name``. It also determines how other
-matrix servers will reach yours for `Federation`_. For a test configuration,
-set this to the hostname of your server. For a more production-ready setup, you
-will probably want to specify your domain (``example.com``) rather than a
-matrix-specific hostname here (in the same way that your email address is
-probably ``user@example.com`` rather than ``user@email.example.com``) - but
-doing so may require more advanced setup - see `Setting up
-Federation`_. Beware that the server name cannot be changed later.
-
-This command will generate you a config file that you can then customise, but it will
-also generate a set of keys for you. These keys will allow your Home Server to
-identify itself to other Home Servers, so don't lose or delete them. It would be
-wise to back them up somewhere safe. (If, for whatever reason, you do need to
-change your Home Server's keys, you may find that other Home Servers have the
-old key cached. If you update the signing key, you should change the name of the
-key in the ``<server name>.signing.key`` file (the second word) to something
-different. See `the spec`__ for more information on key management.)
-
-.. __: `key_management`_
-
-The default configuration exposes two HTTP ports: 8008 and 8448. Port 8008 is
-configured without TLS; it should be behind a reverse proxy for TLS/SSL
-termination on port 443 which in turn should be used for clients. Port 8448
-is configured to use TLS with a self-signed certificate. If you would like
-to do initial test with a client without having to setup a reverse proxy,
-you can temporarly use another certificate. (Note that a self-signed
-certificate is fine for `Federation`_). You can do so by changing
-``tls_certificate_path``, ``tls_private_key_path`` and ``tls_dh_params_path``
-in ``homeserver.yaml``; alternatively, you can use a reverse-proxy, but be sure
-to read `Using a reverse proxy with Synapse`_ when doing so.
-
-Apart from port 8448 using TLS, both ports are the same in the default
-configuration.
-
-Registering a user
-------------------
-
-You will need at least one user on your server in order to use a Matrix
-client. Users can be registered either `via a Matrix client`__, or via a
-commandline script.
-
-.. __: `client-user-reg`_
-
-To get started, it is easiest to use the command line to register new users::
-
-    $ source ~/synapse/env/bin/activate
-    $ synctl start # if not already running
-    $ register_new_matrix_user -c homeserver.yaml https://localhost:8448
-    New user localpart: erikj
-    Password:
-    Confirm password:
-    Make admin [no]:
-    Success!
-
-This process uses a setting ``registration_shared_secret`` in
-``homeserver.yaml``, which is shared between Synapse itself and the
-``register_new_matrix_user`` script. It doesn't matter what it is (a random
-value is generated by ``--generate-config``), but it should be kept secret, as
-anyone with knowledge of it can register users on your server even if
-``enable_registration`` is ``false``.
-
-Setting up a TURN server
-------------------------
-
-For reliable VoIP calls to be routed via this homeserver, you MUST configure
-a TURN server.  See `<docs/turn-howto.rst>`_ for details.
-
-Running Synapse
-===============
-
-To actually run your new homeserver, pick a working directory for Synapse to
-run (e.g. ``~/synapse``), and::
-
-    cd ~/synapse
-    source env/bin/activate
-    synctl start
 
 Connecting to Synapse from a client
 ===================================
@@ -281,10 +95,11 @@ following the recommended setup, or ``https://localhost:8448`` - remember to spe
 port (``:8448``) if not ``:443`` unless you changed the configuration. (Leave the identity
 server as the default - see `Identity servers`_.)
 
-If using port 8448 you will run into errors until you accept the self-signed
-certificate. You can easily do this by going to ``https://localhost:8448``
+If using port 8448 you will run into errors if you are using a self-signed
+certificate. To overcome this, simply go to ``https://localhost:8448``
 directly with your browser and accept the presented certificate. You can then
-go back in your web client and proceed further.
+go back in your web client and proceed further. Valid federation certificates
+should not have this problem.
 
 If all goes well you should at least be able to log in, create a room, and
 start sending messages.
@@ -312,6 +127,12 @@ create the account. Your name will take the form of::
 As when logging in, you will need to specify a "Custom server".  Specify your
 desired ``localpart`` in the 'User name' box.
 
+ACME setup
+==========
+
+For details on having Synapse manage your federation TLS certificates
+automatically, please see `<docs/ACME.md>`_.
+
 
 Security Note
 =============
@@ -329,151 +150,11 @@ server on the same domain.
 See https://github.com/vector-im/riot-web/issues/1977 and
 https://developer.github.com/changes/2014-04-25-user-content-security for more details.
 
-
-Platform-Specific Instructions
-==============================
-
-Debian
-------
-
-Matrix provides official Debian packages via apt from https://matrix.org/packages/debian/.
-Note that these packages do not include a client - choose one from
-https://matrix.org/docs/projects/try-matrix-now.html (or build your own with one of our SDKs :)
-
-Fedora
-------
-
-Synapse is in the Fedora repositories as ``matrix-synapse``::
-
-    sudo dnf install matrix-synapse
-
-Oleg Girko provides Fedora RPMs at
-https://obs.infoserver.lv/project/monitor/matrix-synapse
-
-OpenSUSE
---------
-
-Synapse is in the OpenSUSE repositories as ``matrix-synapse``::
-
-    sudo zypper install matrix-synapse
-
-SUSE Linux Enterprise Server
-----------------------------
-
-Unofficial package are built for SLES 15 in the openSUSE:Backports:SLE-15 repository at
-https://download.opensuse.org/repositories/openSUSE:/Backports:/SLE-15/standard/
-
-ArchLinux
----------
-
-The quickest way to get up and running with ArchLinux is probably with the community package
-https://www.archlinux.org/packages/community/any/matrix-synapse/, which should pull in most of
-the necessary dependencies.
-
-pip may be outdated (6.0.7-1 and needs to be upgraded to 6.0.8-1 )::
-
-    sudo pip install --upgrade pip
-
-If you encounter an error with lib bcrypt causing an Wrong ELF Class:
-ELFCLASS32 (x64 Systems), you may need to reinstall py-bcrypt to correctly
-compile it under the right architecture. (This should not be needed if
-installing under virtualenv)::
-
-    sudo pip uninstall py-bcrypt
-    sudo pip install py-bcrypt
-
-FreeBSD
--------
-
-Synapse can be installed via FreeBSD Ports or Packages contributed by Brendan Molloy from:
-
- - Ports: ``cd /usr/ports/net-im/py-matrix-synapse && make install clean``
- - Packages: ``pkg install py27-matrix-synapse``
-
-
-OpenBSD
--------
-
-There is currently no port for OpenBSD. Additionally, OpenBSD's security
-settings require a slightly more difficult installation process.
-
-1) Create a new directory in ``/usr/local`` called ``_synapse``. Also, create a
-   new user called ``_synapse`` and set that directory as the new user's home.
-   This is required because, by default, OpenBSD only allows binaries which need
-   write and execute permissions on the same memory space to be run from
-   ``/usr/local``.
-2) ``su`` to the new ``_synapse`` user and change to their home directory.
-3) Create a new virtualenv: ``virtualenv -p python2.7 ~/.synapse``
-4) Source the virtualenv configuration located at
-   ``/usr/local/_synapse/.synapse/bin/activate``. This is done in ``ksh`` by
-   using the ``.`` command, rather than ``bash``'s ``source``.
-5) Optionally, use ``pip`` to install ``lxml``, which Synapse needs to parse
-   webpages for their titles.
-6) Use ``pip`` to install this repository: ``pip install matrix-synapse``
-7) Optionally, change ``_synapse``'s shell to ``/bin/false`` to reduce the
-   chance of a compromised Synapse server being used to take over your box.
-
-After this, you may proceed with the rest of the install directions.
-
-NixOS
------
-
-Robin Lambertz has packaged Synapse for NixOS at:
-https://github.com/NixOS/nixpkgs/blob/master/nixos/modules/services/misc/matrix-synapse.nix
-
-Windows Install
----------------
-
-If you wish to run or develop Synapse on Windows, the Windows Subsystem For
-Linux provides a Linux environment on Windows 10 which is capable of using the
-Debian, Fedora, or source installation methods. More information about WSL can
-be found at https://docs.microsoft.com/en-us/windows/wsl/install-win10 for
-Windows 10 and https://docs.microsoft.com/en-us/windows/wsl/install-on-server
-for Windows Server.
-
 Troubleshooting
 ===============
 
-Troubleshooting Installation
-----------------------------
-
-Synapse requires pip 8 or later, so if your OS provides too old a version you
-may need to manually upgrade it::
-
-    sudo pip install --upgrade pip
-
-Installing may fail with ``Could not find any downloads that satisfy the requirement pymacaroons-pynacl (from matrix-synapse==0.12.0)``.
-You can fix this by manually upgrading pip and virtualenv::
-
-    sudo pip install --upgrade virtualenv
-
-You can next rerun ``virtualenv -p python3 synapse`` to update the virtual env.
-
-Installing may fail during installing virtualenv with ``InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning.``
-You can fix this  by manually installing ndg-httpsclient::
-
-    pip install --upgrade ndg-httpsclient
-
-Installing may fail with ``mock requires setuptools>=17.1. Aborting installation``.
-You can fix this by upgrading setuptools::
-
-    pip install --upgrade setuptools
-
-If pip crashes mid-installation for reason (e.g. lost terminal), pip may
-refuse to run until you remove the temporary installation directory it
-created. To reset the installation::
-
-    rm -rf /tmp/pip_install_matrix
-
-pip seems to leak *lots* of memory during installation.  For instance, a Linux
-host with 512MB of RAM may run out of memory whilst installing Twisted.  If this
-happens, you will have to individually install the dependencies which are
-failing, e.g.::
-
-    pip install twisted
-
 Running out of File Handles
-~~~~~~~~~~~~~~~~~~~~~~~~~~~
+---------------------------
 
 If synapse runs out of filehandles, it typically fails badly - live-locking
 at 100% CPU, and/or failing to accept new TCP connections (blocking the
@@ -515,7 +196,7 @@ Federation is the process by which users on different servers can participate
 in the same room. For this to work, those other servers must be able to contact
 yours to send messages.
 
-As explained in `Configuring synapse`_, the ``server_name`` in your
+The ``server_name`` in your
 ``homeserver.yaml`` file determines the way that other servers will reach
 yours. By default, they will treat it as a hostname and try to connect to
 port 8448. This is easy to set up and will work with the default configuration,
@@ -527,9 +208,7 @@ you to run your server on a machine that might not have the same name as your
 domain name. For example, you might want to run your server at
 ``synapse.example.com``, but have your Matrix user-ids look like
 ``@user:example.com``. (A SRV record also allows you to change the port from
-the default 8448. However, if you are thinking of using a reverse-proxy on the
-federation port, which is not recommended, be sure to read
-`Reverse-proxying the federation port`_ first.)
+the default 8448).
 
 To use a SRV record, first create your SRV record and publish it in DNS. This
 should have the format ``_matrix._tcp.<yourdomain.com> <ttl> IN SRV 10 0 <port>
@@ -567,6 +246,8 @@ Troubleshooting
 You can use the federation tester to check if your homeserver is all set:
 ``https://matrix.org/federationtester/api/report?server_name=<your_server_name>``
 If any of the attributes under "checks" is false, federation won't work.
+There is also a nicer interface available from a community member at
+`<https://neo.lain.haus/fed-tester>`_.
 
 The typical failure mode with federation is that when you try to join a room,
 it is rejected with "401: Unauthorized". Generally this means that other
@@ -575,8 +256,6 @@ complicated dance which requires connections in both directions).
 
 So, things to check are:
 
-* If you are trying to use a reverse-proxy, read `Reverse-proxying the
-  federation port`_.
 * If you are not using a SRV record, check that your ``server_name`` (the part
   of your user-id after the ``:``) matches your hostname, and that port 8448 on
   that hostname is reachable from outside your network.
@@ -631,14 +310,8 @@ port. Indeed, clients will use port 443 by default, whereas servers default to
 port 8448. Where these are different, we refer to the 'client port' and the
 'federation port'.
 
-The next most important thing to know is that using a reverse-proxy on the
-federation port has a number of pitfalls. It is possible, but be sure to read
-`Reverse-proxying the federation port`_.
-
-The recommended setup is therefore to configure your reverse-proxy on port 443
-to port 8008 of synapse for client connections, but to also directly expose port
-8448 for server-server connections. All the Matrix endpoints begin ``/_matrix``,
-so an example nginx configuration might look like::
+All Matrix endpoints begin with ``/_matrix``, so an example nginx
+configuration for forwarding client connections to Synapse might look like::
 
   server {
       listen 443 ssl;
@@ -679,64 +352,6 @@ Having done so, you can then use ``https://matrix.example.com`` (instead of
 ``https://matrix.example.com:8448``) as the "Custom server" when `Connecting to
 Synapse from a client`_.
 
-Reverse-proxying the federation port
-------------------------------------
-
-There are two issues to consider before using a reverse-proxy on the federation
-port:
-
-* Due to the way SSL certificates are managed in the Matrix federation protocol
-  (see `spec`__), Synapse needs to be configured with the path to the SSL
-  certificate, *even if you do not terminate SSL at Synapse*.
-
-  .. __: `key_management`_
-
-* Until v0.33.3, Synapse did not support SNI on the federation port
-  (`bug #1491 <https://github.com/matrix-org/synapse/issues/1491>`_). This bug
-  is now fixed, but means that federating with older servers can be unreliable
-  when using name-based virtual hosting.
-
-Furthermore, a number of the normal reasons for using a reverse-proxy do not
-apply:
-
-* Other servers will connect on port 8448 by default, so there is no need to
-  listen on port 443 (for federation, at least), which avoids the need for root
-  privileges and virtual hosting.
-
-* A self-signed SSL certificate is fine for federation, so there is no need to
-  automate renewals. (The certificate generated by ``--generate-config`` is
-  valid for 10 years.)
-
-If you want to set up a reverse-proxy on the federation port despite these
-caveats, you will need to do the following:
-
-* In ``homeserver.yaml``, set ``tls_certificate_path`` to the path to the SSL
-  certificate file used by your reverse-proxy, and set ``no_tls`` to ``True``.
-  (``tls_private_key_path`` will be ignored if ``no_tls`` is ``True``.)
-
-* In your reverse-proxy configuration:
-
-  * If there are other virtual hosts on the same port, make sure that the
-    *default* one uses the certificate configured above.
-
-  * Forward ``/_matrix`` to Synapse.
-
-* If your reverse-proxy is not listening on port 8448, publish a SRV record to
-  tell other servers how to find you. See `Setting up Federation`_.
-
-When updating the SSL certificate, just update the file pointed to by
-``tls_certificate_path`` and then restart Synapse. (You may like to use a symbolic link
-to help make this process atomic.)
-
-The most common mistake when setting up federation is not to tell Synapse about
-your SSL certificate. To check it, you can visit
-``https://matrix.org/federationtester/api/report?server_name=<your_server_name>``.
-Unfortunately, there is no UI for this yet, but, you should see
-``"MatchingTLSFingerprint": true``. If not, check that
-``Certificates[0].SHA256Fingerprint`` (the fingerprint of the certificate
-presented by your reverse-proxy) matches ``Keys.tls_fingerprints[0].sha256``
-(the fingerprint of the certificate Synapse is using).
-
 
 Identity Servers
 ================
@@ -768,24 +383,6 @@ an email address with your account, or send an invite to another user via their
 email address.
 
 
-URL Previews
-============
-
-Synapse 0.15.0 introduces a new API for previewing URLs at
-``/_matrix/media/r0/preview_url``.  This is disabled by default.  To turn it on
-you must enable the ``url_preview_enabled: True`` config parameter and
-explicitly specify the IP ranges that Synapse is not allowed to spider for
-previewing in the ``url_preview_ip_range_blacklist`` configuration parameter.
-This is critical from a security perspective to stop arbitrary Matrix users
-spidering 'internal' URLs on your network.  At the very least we recommend that
-your loopback and RFC1918 IP addresses are blacklisted.
-
-This also requires the optional lxml and netaddr python dependencies to be
-installed.  This in turn requires the libxml2 library to be available - on
-Debian/Ubuntu this means ``apt-get install libxml2-dev``, or equivalent for
-your OS.
-
-
 Password reset
 ==============
 
@@ -796,8 +393,7 @@ A manual password reset can be done via direct database access as follows.
 
 First calculate the hash of the new password::
 
-    $ source ~/.synapse/bin/activate
-    $ ./scripts/hash_password
+    $ ~/synapse/env/bin/hash_password
     Password:
     Confirm password:
     $2a$12$xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
@@ -888,5 +484,3 @@ by installing the ``libjemalloc1`` package and adding this line to
 ``/etc/default/matrix-synapse``::
 
     LD_PRELOAD=/usr/lib/x86_64-linux-gnu/libjemalloc.so.1
-
-.. _`key_management`: https://matrix.org/docs/spec/server_server/unstable.html#retrieving-server-keys
diff --git a/UPGRADE.rst b/UPGRADE.rst
index b214a155..36434772 100644
--- a/UPGRADE.rst
+++ b/UPGRADE.rst
@@ -5,20 +5,20 @@ Before upgrading check if any special steps are required to upgrade from the
 what you currently have installed to current version of synapse. The extra
 instructions that may be required are listed later in this document.
 
-1. If synapse was installed in a virtualenv then active that virtualenv before
-   upgrading. If synapse is installed in a virtualenv in ``~/.synapse/`` then
+1. If synapse was installed in a virtualenv then activate that virtualenv before
+   upgrading. If synapse is installed in a virtualenv in ``~/synapse/env`` then
    run:
 
    .. code:: bash
 
-       source ~/.synapse/bin/activate
+       source ~/synapse/env/bin/activate
 
 2. If synapse was installed using pip then upgrade to the latest version by
    running:
 
    .. code:: bash
 
-       pip install --upgrade --process-dependency-links matrix-synapse
+       pip install --upgrade matrix-synapse[all]
 
        # restart synapse
        synctl restart
@@ -31,8 +31,9 @@ instructions that may be required are listed later in this document.
 
        # Pull the latest version of the master branch.
        git pull
-       # Update the versions of synapse's python dependencies.
-       python synapse/python_dependencies.py | xargs pip install --upgrade
+
+       # Update synapse and its python dependencies.
+       pip install --upgrade .[all]
 
        # restart synapse
        ./synctl restart
@@ -48,6 +49,16 @@ returned by the Client-Server API:
     # configured on port 443.
     curl -kv https://<host.name>/_matrix/client/versions 2>&1 | grep "Server:"
 
+Upgrading to v0.99.0
+====================
+
+Please be aware that, before Synapse v1.0 is released around March 2019, you
+will need to replace any self-signed certificates with those verified by a
+root CA. Information on how to do so can be found at `the ACME docs
+<docs/ACME.md>`_.
+
+For more information on configuring TLS certificates see the `FAQ <https://github.com/matrix-org/synapse/blob/master/docs/MSC1711_certificates_FAQ.md>`_
+
 Upgrading to v0.34.0
 ====================
 
diff --git a/contrib/prometheus/README b/contrib/prometheus/README.md
index 7b733172..e646cb7e 100644
--- a/contrib/prometheus/README
+++ b/contrib/prometheus/README.md
@@ -6,8 +6,10 @@ To use it, first install prometheus by following the instructions at
   http://prometheus.io/
 
 ### for Prometheus v1
+
 Add a new job to the main prometheus.conf file:
 
+```yaml
   job: {
     name: "synapse"
 
@@ -15,10 +17,12 @@ Add a new job to the main prometheus.conf file:
       target: "http://SERVER.LOCATION.HERE:PORT/_synapse/metrics"
     }
   }
+```
 
 ### for Prometheus v2
 Add a new job to the main prometheus.yml file:
 
+```yaml
   - job_name: "synapse"
     metrics_path: "/_synapse/metrics"
     # when endpoint uses https:
@@ -26,11 +30,14 @@ Add a new job to the main prometheus.yml file:
 
     static_configs:
     - targets: ['SERVER.LOCATION:PORT']
+```
 
 To use `synapse.rules` add
 
+```yaml
     rule_files:
       - "/PATH/TO/synapse-v2.rules"
+```
 
 Metrics are disabled by default when running synapse; they must be enabled
 with the 'enable-metrics' option, either in the synapse config file or as a
diff --git a/debian/build_virtualenv b/debian/build_virtualenv
index 83346c40..bead3ebc 100755
--- a/debian/build_virtualenv
+++ b/debian/build_virtualenv
@@ -6,7 +6,16 @@
 set -e
 
 export DH_VIRTUALENV_INSTALL_ROOT=/opt/venvs
-SNAKE=/usr/bin/python3
+
+# make sure that the virtualenv links to the specific version of python, by
+# dereferencing the python3 symlink.
+#
+# Otherwise, if somebody tries to install (say) the stretch package on buster,
+# they will get a confusing error about "No module named 'synapse'", because
+# python won't look in the right directory. At least this way, the error will
+# be a *bit* more obvious.
+#
+SNAKE=`readlink -e /usr/bin/python3`
 
 # try to set the CFLAGS so any compiled C extensions are compiled with the most
 # generic as possible x64 instructions, so that compiling it on a new Intel chip
@@ -36,6 +45,10 @@ dh_virtualenv \
     --extra-pip-arg="--compile" \
     --extras="all"
 
+PACKAGE_BUILD_DIR="debian/matrix-synapse-py3"
+VIRTUALENV_DIR="${PACKAGE_BUILD_DIR}${DH_VIRTUALENV_INSTALL_ROOT}/matrix-synapse"
+TARGET_PYTHON="${VIRTUALENV_DIR}/bin/python"
+
 # we copy the tests to a temporary directory so that we can put them on the
 # PYTHONPATH without putting the uninstalled synapse on the pythonpath.
 tmpdir=`mktemp -d`
@@ -44,5 +57,35 @@ trap "rm -r $tmpdir" EXIT
 cp -r tests "$tmpdir"
 
 PYTHONPATH="$tmpdir" \
-    debian/matrix-synapse-py3/opt/venvs/matrix-synapse/bin/python \
-        -B -m twisted.trial --reporter=text -j2 tests
+    "${TARGET_PYTHON}" -B -m twisted.trial --reporter=text -j2 tests
+
+# build the config file
+"${TARGET_PYTHON}" -B "${VIRTUALENV_DIR}/bin/generate_config" \
+        --config-dir="/etc/matrix-synapse" \
+        --data-dir="/var/lib/matrix-synapse" |
+    perl -pe '
+# tweak the paths to the tls certs and signing keys
+/^tls_.*_path:/ and s/SERVERNAME/homeserver/;
+/^signing_key_path:/ and s/SERVERNAME/homeserver/;
+
+# tweak the pid file location
+/^pid_file:/ and s#:.*#: "/var/run/matrix-synapse.pid"#;
+
+# tweak the path to the log config
+/^log_config:/ and s/SERVERNAME\.log\.config/log.yaml/;
+
+# tweak the path to the media store
+/^media_store_path:/ and s#/media_store#/media#;
+
+# remove the server_name setting, which is set in a separate file
+/^server_name:/ and $_ = "#\n# This is set in /etc/matrix-synapse/conf.d/server_name.yaml for Debian installations.\n# $_";
+
+# remove the report_stats setting, which is set in a separate file
+/^# report_stats:/ and $_ = "";
+
+' > "${PACKAGE_BUILD_DIR}/etc/matrix-synapse/homeserver.yaml"
+
+
+# add a dependency on the right version of python to substvars.
+PYPKG=`basename $SNAKE`
+echo "synapse:pydepends=$PYPKG" >> debian/matrix-synapse-py3.substvars
diff --git a/debian/changelog b/debian/changelog
index 921f7021..04b5d690 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,21 @@
+matrix-synapse-py3 (0.99.0) stable; urgency=medium
+
+  * New synapse release 0.99.0
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 5 Feb 2019 18:25:00 +0000
+
+matrix-synapse-py3 (0.34.1.1++1) stable; urgency=medium
+
+  * Update conflicts specifications to allow smoother transition from matrix-synapse.
+
+ -- Synapse Packaging team <packages@matrix.org>  Sat, 12 Jan 2019 12:58:35 +0000
+
+matrix-synapse-py3 (0.34.1.1) stable; urgency=high
+
+  * New synapse release 0.34.1.1
+
+ -- Synapse Packaging team <packages@matrix.org>  Thu, 10 Jan 2019 15:04:52 +0000
+
 matrix-synapse-py3 (0.34.1+1) stable; urgency=medium
 
   * Remove 'Breaks: matrix-synapse-ldap3'. (matrix-synapse-py3 includes
diff --git a/debian/control b/debian/control
index 634f0428..4abfa020 100644
--- a/debian/control
+++ b/debian/control
@@ -19,16 +19,16 @@ Homepage: https://github.com/matrix-org/synapse
 Package: matrix-synapse-py3
 Architecture: amd64
 Provides: matrix-synapse
-Breaks:
- matrix-synapse (<< 0.34.0-0matrix2),
- matrix-synapse (>= 0.34.0-1),
+Conflicts:
+ matrix-synapse (<< 0.34.0.1-0matrix2),
+ matrix-synapse (>= 0.34.0.1-1),
 Pre-Depends: dpkg (>= 1.16.1)
 Depends:
  adduser,
  debconf,
  python3-distutils|libpython3-stdlib (<< 3.6),
- python3,
  ${misc:Depends},
+ ${synapse:pydepends},
 # some of our scripts use perl, but none of them are important,
 # so we put perl:Depends in Suggests rather than Depends.
 Suggests:
diff --git a/debian/homeserver.yaml b/debian/homeserver.yaml
deleted file mode 100644
index 188a2d54..00000000
--- a/debian/homeserver.yaml
+++ /dev/null
@@ -1,617 +0,0 @@
-# vim:ft=yaml
-# PEM encoded X509 certificate for TLS.
-# You can replace the self-signed certificate that synapse
-# autogenerates on launch with your own SSL certificate + key pair
-# if you like.  Any required intermediary certificates can be
-# appended after the primary certificate in hierarchical order.
-tls_certificate_path: "/etc/matrix-synapse/homeserver.tls.crt"
-
-# PEM encoded private key for TLS
-tls_private_key_path: "/etc/matrix-synapse/homeserver.tls.key"
-
-# PEM dh parameters for ephemeral keys
-tls_dh_params_path: "/etc/matrix-synapse/homeserver.tls.dh"
-
-# Don't bind to the https port
-no_tls: False
-
-# List of allowed TLS fingerprints for this server to publish along
-# with the signing keys for this server. Other matrix servers that
-# make HTTPS requests to this server will check that the TLS
-# certificates returned by this server match one of the fingerprints.
-#
-# Synapse automatically adds the fingerprint of its own certificate
-# to the list. So if federation traffic is handled directly by synapse
-# then no modification to the list is required.
-#
-# If synapse is run behind a load balancer that handles the TLS then it
-# will be necessary to add the fingerprints of the certificates used by
-# the loadbalancers to this list if they are different to the one
-# synapse is using.
-#
-# Homeservers are permitted to cache the list of TLS fingerprints
-# returned in the key responses up to the "valid_until_ts" returned in
-# key. It may be necessary to publish the fingerprints of a new
-# certificate and wait until the "valid_until_ts" of the previous key
-# responses have passed before deploying it.
-#
-# You can calculate a fingerprint from a given TLS listener via:
-# openssl s_client -connect $host:$port < /dev/null 2> /dev/null |
-#   openssl x509 -outform DER | openssl sha256 -binary | base64 | tr -d '='
-# or by checking matrix.org/federationtester/api/report?server_name=$host
-#
-tls_fingerprints: []
-# tls_fingerprints: [{"sha256": "<base64_encoded_sha256_fingerprint>"}]
-
-
-## Server ##
-
-# When running as a daemon, the file to store the pid in
-pid_file: "/var/run/matrix-synapse.pid"
-
-# CPU affinity mask. Setting this restricts the CPUs on which the
-# process will be scheduled. It is represented as a bitmask, with the
-# lowest order bit corresponding to the first logical CPU and the
-# highest order bit corresponding to the last logical CPU. Not all CPUs
-# may exist on a given system but a mask may specify more CPUs than are
-# present.
-#
-# For example:
-#    0x00000001  is processor #0,
-#    0x00000003  is processors #0 and #1,
-#    0xFFFFFFFF  is all processors (#0 through #31).
-#
-# Pinning a Python process to a single CPU is desirable, because Python
-# is inherently single-threaded due to the GIL, and can suffer a
-# 30-40% slowdown due to cache blow-out and thread context switching
-# if the scheduler happens to schedule the underlying threads across
-# different cores. See
-# https://www.mirantis.com/blog/improve-performance-python-programs-restricting-single-cpu/.
-#
-# cpu_affinity: 0xFFFFFFFF
-
-# The path to the web client which will be served at /_matrix/client/
-# if 'webclient' is configured under the 'listeners' configuration.
-#
-# web_client_location: "/path/to/web/root"
-
-# The public-facing base URL for the client API (not including _matrix/...)
-# public_baseurl: https://example.com:8448/
-
-# Set the soft limit on the number of file descriptors synapse can use
-# Zero is used to indicate synapse should set the soft limit to the
-# hard limit.
-soft_file_limit: 0
-
-# The GC threshold parameters to pass to `gc.set_threshold`, if defined
-# gc_thresholds: [700, 10, 10]
-
-# Set the limit on the returned events in the timeline in the get
-# and sync operations. The default value is -1, means no upper limit.
-# filter_timeline_limit: 5000
-
-# Whether room invites to users on this server should be blocked
-# (except those sent by local server admins). The default is False.
-# block_non_admin_invites: True
-
-# Restrict federation to the following whitelist of domains.
-# N.B. we recommend also firewalling your federation listener to limit
-# inbound federation traffic as early as possible, rather than relying
-# purely on this application-layer restriction.  If not specified, the
-# default is to whitelist everything.
-#
-# federation_domain_whitelist:
-#  - lon.example.com
-#  - nyc.example.com
-#  - syd.example.com
-
-# List of ports that Synapse should listen on, their purpose and their
-# configuration.
-listeners:
-  # Main HTTPS listener
-  # For when matrix traffic is sent directly to synapse.
-  -
-    # The port to listen for HTTPS requests on.
-    port: 8448
-
-    # Local addresses to listen on.
-    # On Linux and Mac OS, `::` will listen on all IPv4 and IPv6
-    # addresses by default. For most other OSes, this will only listen
-    # on IPv6.
-    bind_addresses:
-      - '::'
-      - '0.0.0.0'
-
-    # This is a 'http' listener, allows us to specify 'resources'.
-    type: http
-
-    tls: true
-
-    # Use the X-Forwarded-For (XFF) header as the client IP and not the
-    # actual client IP.
-    x_forwarded: false
-
-    # List of HTTP resources to serve on this listener.
-    resources:
-      -
-        # List of resources to host on this listener.
-        names:
-          - client     # The client-server APIs, both v1 and v2
-          - webclient  # The bundled webclient.
-
-        # Should synapse compress HTTP responses to clients that support it?
-        # This should be disabled if running synapse behind a load balancer
-        # that can do automatic compression.
-        compress: true
-
-      - names: [federation]  # Federation APIs
-        compress: false
-
-    # optional list of additional endpoints which can be loaded via
-    # dynamic modules
-    # additional_resources:
-    #   "/_matrix/my/custom/endpoint":
-    #     module: my_module.CustomRequestHandler
-    #     config: {}
-
-  # Unsecure HTTP listener,
-  # For when matrix traffic passes through loadbalancer that unwraps TLS.
-  - port: 8008
-    tls: false
-    bind_addresses: ['::', '0.0.0.0']
-    type: http
-
-    x_forwarded: false
-
-    resources:
-      - names: [client, webclient]
-        compress: true
-      - names: [federation]
-        compress: false
-
-  # Turn on the twisted ssh manhole service on localhost on the given
-  # port.
-  # - port: 9000
-  #   bind_addresses: ['::1', '127.0.0.1']
-  #   type: manhole
-
-
-# Database configuration
-database:
-  # The database engine name
-  name: "sqlite3"
-  # Arguments to pass to the engine
-  args:
-    # Path to the database
-    database: "/var/lib/matrix-synapse/homeserver.db"
-
-# Number of events to cache in memory.
-event_cache_size: "10K"
-
-
-# A yaml python logging config file
-log_config: "/etc/matrix-synapse/log.yaml"
-
-
-
-## Ratelimiting ##
-
-# Number of messages a client can send per second
-rc_messages_per_second: 0.2
-
-# Number of message a client can send before being throttled
-rc_message_burst_count: 10.0
-
-# The federation window size in milliseconds
-federation_rc_window_size: 1000
-
-# The number of federation requests from a single server in a window
-# before the server will delay processing the request.
-federation_rc_sleep_limit: 10
-
-# The duration in milliseconds to delay processing events from
-# remote servers by if they go over the sleep limit.
-federation_rc_sleep_delay: 500
-
-# The maximum number of concurrent federation requests allowed
-# from a single server
-federation_rc_reject_limit: 50
-
-# The number of federation requests to concurrently process from a
-# single server
-federation_rc_concurrent: 3
-
-
-
-# Directory where uploaded images and attachments are stored.
-media_store_path: "/var/lib/matrix-synapse/media"
-
-# Media storage providers allow media to be stored in different
-# locations.
-# media_storage_providers:
-# - module: file_system
-#   # Whether to write new local files.
-#   store_local: false
-#   # Whether to write new remote media
-#   store_remote: false
-#   # Whether to block upload requests waiting for write to this
-#   # provider to complete
-#   store_synchronous: false
-#   config:
-#     directory: /mnt/some/other/directory
-
-# Directory where in-progress uploads are stored.
-uploads_path: "/var/lib/matrix-synapse/uploads"
-
-# The largest allowed upload size in bytes
-max_upload_size: "10M"
-
-# Maximum number of pixels that will be thumbnailed
-max_image_pixels: "32M"
-
-# Whether to generate new thumbnails on the fly to precisely match
-# the resolution requested by the client. If true then whenever
-# a new resolution is requested by the client the server will
-# generate a new thumbnail. If false the server will pick a thumbnail
-# from a precalculated list.
-dynamic_thumbnails: false
-
-# List of thumbnail to precalculate when an image is uploaded.
-thumbnail_sizes:
-- width: 32
-  height: 32
-  method: crop
-- width: 96
-  height: 96
-  method: crop
-- width: 320
-  height: 240
-  method: scale
-- width: 640
-  height: 480
-  method: scale
-- width: 800
-  height: 600
-  method: scale
-
-# Is the preview URL API enabled?  If enabled, you *must* specify
-# an explicit url_preview_ip_range_blacklist of IPs that the spider is
-# denied from accessing.
-url_preview_enabled: False
-
-# List of IP address CIDR ranges that the URL preview spider is denied
-# from accessing.  There are no defaults: you must explicitly
-# specify a list for URL previewing to work.  You should specify any
-# internal services in your network that you do not want synapse to try
-# to connect to, otherwise anyone in any Matrix room could cause your
-# synapse to issue arbitrary GET requests to your internal services,
-# causing serious security issues.
-#
-# url_preview_ip_range_blacklist:
-# - '127.0.0.0/8'
-# - '10.0.0.0/8'
-# - '172.16.0.0/12'
-# - '192.168.0.0/16'
-# - '100.64.0.0/10'
-# - '169.254.0.0/16'
-#
-# List of IP address CIDR ranges that the URL preview spider is allowed
-# to access even if they are specified in url_preview_ip_range_blacklist.
-# This is useful for specifying exceptions to wide-ranging blacklisted
-# target IP ranges - e.g. for enabling URL previews for a specific private
-# website only visible in your network.
-#
-# url_preview_ip_range_whitelist:
-# - '192.168.1.1'
-
-# Optional list of URL matches that the URL preview spider is
-# denied from accessing.  You should use url_preview_ip_range_blacklist
-# in preference to this, otherwise someone could define a public DNS
-# entry that points to a private IP address and circumvent the blacklist.
-# This is more useful if you know there is an entire shape of URL that
-# you know that will never want synapse to try to spider.
-#
-# Each list entry is a dictionary of url component attributes as returned
-# by urlparse.urlsplit as applied to the absolute form of the URL.  See
-# https://docs.python.org/2/library/urlparse.html#urlparse.urlsplit
-# The values of the dictionary are treated as an filename match pattern
-# applied to that component of URLs, unless they start with a ^ in which
-# case they are treated as a regular expression match.  If all the
-# specified component matches for a given list item succeed, the URL is
-# blacklisted.
-#
-# url_preview_url_blacklist:
-# # blacklist any URL with a username in its URI
-# - username: '*'
-#
-# # blacklist all *.google.com URLs
-# - netloc: 'google.com'
-# - netloc: '*.google.com'
-#
-# # blacklist all plain HTTP URLs
-# - scheme: 'http'
-#
-# # blacklist http(s)://www.acme.com/foo
-# - netloc: 'www.acme.com'
-#   path: '/foo'
-#
-# # blacklist any URL with a literal IPv4 address
-# - netloc: '^[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+$'
-
-# The largest allowed URL preview spidering size in bytes
-max_spider_size: "10M"
-
-
-
-
-## Captcha ##
-# See docs/CAPTCHA_SETUP for full details of configuring this.
-
-# This Home Server's ReCAPTCHA public key.
-recaptcha_public_key: "YOUR_PUBLIC_KEY"
-
-# This Home Server's ReCAPTCHA private key.
-recaptcha_private_key: "YOUR_PRIVATE_KEY"
-
-# Enables ReCaptcha checks when registering, preventing signup
-# unless a captcha is answered. Requires a valid ReCaptcha
-# public/private key.
-enable_registration_captcha: False
-
-# A secret key used to bypass the captcha test entirely.
-#captcha_bypass_secret: "YOUR_SECRET_HERE"
-
-# The API endpoint to use for verifying m.login.recaptcha responses.
-recaptcha_siteverify_api: "https://www.google.com/recaptcha/api/siteverify"
-
-
-## Turn ##
-
-# The public URIs of the TURN server to give to clients
-turn_uris: []
-
-# The shared secret used to compute passwords for the TURN server
-turn_shared_secret: "YOUR_SHARED_SECRET"
-
-# The Username and password if the TURN server needs them and
-# does not use a token
-#turn_username: "TURNSERVER_USERNAME"
-#turn_password: "TURNSERVER_PASSWORD"
-
-# How long generated TURN credentials last
-turn_user_lifetime: "1h"
-
-# Whether guests should be allowed to use the TURN server.
-# This defaults to True, otherwise VoIP will be unreliable for guests.
-# However, it does introduce a slight security risk as it allows users to
-# connect to arbitrary endpoints without having first signed up for a
-# valid account (e.g. by passing a CAPTCHA).
-turn_allow_guests: False
-
-
-## Registration ##
-
-# Enable registration for new users.
-enable_registration: False
-
-# The user must provide all of the below types of 3PID when registering.
-#
-# registrations_require_3pid:
-#     - email
-#     - msisdn
-
-# Mandate that users are only allowed to associate certain formats of
-# 3PIDs with accounts on this server.
-#
-# allowed_local_3pids:
-#     - medium: email
-#       pattern: ".*@matrix\.org"
-#     - medium: email
-#       pattern: ".*@vector\.im"
-#     - medium: msisdn
-#       pattern: "\+44"
-
-# If set, allows registration by anyone who also has the shared
-# secret, even if registration is otherwise disabled.
-# registration_shared_secret: <PRIVATE STRING>
-
-# Set the number of bcrypt rounds used to generate password hash.
-# Larger numbers increase the work factor needed to generate the hash.
-# The default number is 12 (which equates to 2^12 rounds).
-# N.B. that increasing this will exponentially increase the time required
-# to register or login - e.g. 24 => 2^24 rounds which will take >20 mins.
-bcrypt_rounds: 12
-
-# Allows users to register as guests without a password/email/etc, and
-# participate in rooms hosted on this server which have been made
-# accessible to anonymous users.
-allow_guest_access: False
-
-# The list of identity servers trusted to verify third party
-# identifiers by this server.
-trusted_third_party_id_servers:
-    - matrix.org
-    - vector.im
-    - riot.im
-
-# Users who register on this homeserver will automatically be joined
-# to these rooms
-#auto_join_rooms:
-#    - "#example:example.com"
-
-
-## Metrics ###
-
-# Enable collection and rendering of performance metrics
-enable_metrics: False
-
-## API Configuration ##
-
-# A list of event types that will be included in the room_invite_state
-room_invite_state_types:
-    - "m.room.join_rules"
-    - "m.room.canonical_alias"
-    - "m.room.avatar"
-    - "m.room.name"
-
-
-# A list of application service config file to use
-app_service_config_files: []
-
-
-# macaroon_secret_key: <PRIVATE STRING>
-
-# Used to enable access token expiration.
-expire_access_token: False
-
-## Signing Keys ##
-
-# Path to the signing key to sign messages with
-signing_key_path: "/etc/matrix-synapse/homeserver.signing.key"
-
-# The keys that the server used to sign messages with but won't use
-# to sign new messages. E.g. it has lost its private key
-old_signing_keys: {}
-#  "ed25519:auto":
-#    # Base64 encoded public key
-#    key: "The public part of your old signing key."
-#    # Millisecond POSIX timestamp when the key expired.
-#    expired_ts: 123456789123
-
-# How long key response published by this server is valid for.
-# Used to set the valid_until_ts in /key/v2 APIs.
-# Determines how quickly servers will query to check which keys
-# are still valid.
-key_refresh_interval: "1d" # 1 Day.
-
-# The trusted servers to download signing keys from.
-perspectives:
-  servers:
-    "matrix.org":
-      verify_keys:
-        "ed25519:auto":
-          key: "Noi6WqcDj0QmPxCNQqgezwTlBKrfqehY1u2FyWP9uYw"
-
-
-
-# Enable SAML2 for registration and login. Uses pysaml2
-# config_path:      Path to the sp_conf.py configuration file
-# idp_redirect_url: Identity provider URL which will redirect
-#                   the user back to /login/saml2 with proper info.
-# See pysaml2 docs for format of config.
-#saml2_config:
-#   enabled: true
-#   config_path: "/home/erikj/git/synapse/sp_conf.py"
-#   idp_redirect_url: "http://test/idp"
-
-
-
-# Enable CAS for registration and login.
-#cas_config:
-#   enabled: true
-#   server_url: "https://cas-server.com"
-#   service_url: "https://homeserver.domain.com:8448"
-#   #required_attributes:
-#   #    name: value
-
-
-# The JWT needs to contain a globally unique "sub" (subject) claim.
-#
-# jwt_config:
-#    enabled: true
-#    secret: "a secret"
-#    algorithm: "HS256"
-
-
-
-# Enable password for login.
-password_config:
-   enabled: true
-   # Uncomment and change to a secret random string for extra security.
-   # DO NOT CHANGE THIS AFTER INITIAL SETUP!
-   #pepper: ""
-
-
-
-# Enable sending emails for notification events
-# Defining a custom URL for Riot is only needed if email notifications
-# should contain links to a self-hosted installation of Riot; when set
-# the "app_name" setting is ignored.
-#
-# If your SMTP server requires authentication, the optional smtp_user &
-# smtp_pass variables should be used
-#
-#email:
-#   enable_notifs: false
-#   smtp_host: "localhost"
-#   smtp_port: 25
-#   smtp_user: "exampleusername"
-#   smtp_pass: "examplepassword"
-#   require_transport_security: False
-#   notif_from: "Your Friendly %(app)s Home Server <noreply@example.com>"
-#   app_name: Matrix
-#   template_dir: res/templates
-#   notif_template_html: notif_mail.html
-#   notif_template_text: notif_mail.txt
-#   notif_for_new_users: True
-#   riot_base_url: "http://localhost/riot"
-
-
-# password_providers:
-#     - module: "ldap_auth_provider.LdapAuthProvider"
-#       config:
-#         enabled: true
-#         uri: "ldap://ldap.example.com:389"
-#         start_tls: true
-#         base: "ou=users,dc=example,dc=com"
-#         attributes:
-#            uid: "cn"
-#            mail: "email"
-#            name: "givenName"
-#         #bind_dn:
-#         #bind_password:
-#         #filter: "(objectClass=posixAccount)"
-
-
-
-# Clients requesting push notifications can either have the body of
-# the message sent in the notification poke along with other details
-# like the sender, or just the event ID and room ID (`event_id_only`).
-# If clients choose the former, this option controls whether the
-# notification request includes the content of the event (other details
-# like the sender are still included). For `event_id_only` push, it
-# has no effect.
-
-# For modern android devices the notification content will still appear
-# because it is loaded by the app. iPhone, however will send a
-# notification saying only that a message arrived and who it came from.
-#
-#push:
-#   include_content: true
-
-
-# spam_checker:
-#     module: "my_custom_project.SuperSpamChecker"
-#     config:
-#         example_option: 'things'
-
-
-# Whether to allow non server admins to create groups on this server
-enable_group_creation: false
-
-# If enabled, non server admins can only create groups with local parts
-# starting with this prefix
-# group_creation_prefix: "unofficial/"
-
-
-
-# User Directory configuration
-#
-# 'search_all_users' defines whether to search all users visible to your HS
-# when searching the user directory, rather than limiting to users visible
-# in public rooms.  Defaults to false.  If you set it True, you'll have to run
-# UPDATE user_directory_stream_pos SET stream_id = NULL;
-# on your database to tell it to rebuild the user_directory search indexes.
-#
-#user_directory:
-#   search_all_users: false
diff --git a/debian/install b/debian/install
index d1f42c8b..3d916a97 100644
--- a/debian/install
+++ b/debian/install
@@ -1,2 +1 @@
-debian/homeserver.yaml etc/matrix-synapse
 debian/log.yaml etc/matrix-synapse
diff --git a/demo/demo.tls.dh b/demo/demo.tls.dh
deleted file mode 100644
index cbc58272..00000000
--- a/demo/demo.tls.dh
+++ /dev/null
@@ -1,9 +0,0 @@
-2048-bit DH parameters taken from rfc3526
------BEGIN DH PARAMETERS-----
-MIIBCAKCAQEA///////////JD9qiIWjCNMTGYouA3BzRKQJOCIpnzHQCC76mOxOb
-IlFKCHmONATd75UZs806QxswKwpt8l8UN0/hNW1tUcJF5IW1dmJefsb0TELppjft
-awv/XLb0Brft7jhr+1qJn6WunyQRfEsf5kkoZlHs5Fs9wgB8uKFjvwWY2kg2HFXT
-mmkWP6j9JM9fg2VdI9yjrZYcYvNWIIVSu57VKQdwlpZtZww1Tkq8mATxdGwIyhgh
-fDKQXkYuNs474553LBgOhgObJ4Oi7Aeij7XFXfBvTFLJ3ivL9pVYFxg5lUl86pVq
-5RXSJhiY+gUQFXKOWoqsqmj//////////wIBAg==
------END DH PARAMETERS-----
diff --git a/docker/Dockerfile b/docker/Dockerfile
index 4b739e7d..c35da67a 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -1,3 +1,16 @@
+# Dockerfile to build the matrixdotorg/synapse docker images.
+#
+# To build the image, run `docker build` command from the root of the
+# synapse repository:
+#
+#    docker build -f docker/Dockerfile .
+#
+# There is an optional PYTHON_VERSION build argument which sets the
+# version of python to build against: for example:
+#
+#    docker build -f docker/Dockerfile --build-arg PYTHON_VERSION=3.6 .
+#
+
 ARG PYTHON_VERSION=2
 
 ###
@@ -31,7 +44,10 @@ RUN pip install --prefix="/install" --no-warn-script-location \
 
 # now install synapse and all of the python deps to /install.
 
-COPY . /synapse
+COPY synapse /synapse/synapse/
+COPY scripts /synapse/scripts/
+COPY MANIFEST.in README.rst setup.py synctl /synapse/
+
 RUN pip install --prefix="/install" --no-warn-script-location \
         /synapse[all]
 
@@ -56,6 +72,6 @@ COPY ./docker/conf /conf
 
 VOLUME ["/data"]
 
-EXPOSE 8008/tcp 8448/tcp
+EXPOSE 8008/tcp 8009/tcp 8448/tcp
 
 ENTRYPOINT ["/start.py"]
diff --git a/docker/README.md b/docker/README.md
index 3c00d1e9..3faedf62 100644
--- a/docker/README.md
+++ b/docker/README.md
@@ -1,22 +1,21 @@
 # Synapse Docker
 
-This Docker image will run Synapse as a single process. It does not provide a database
-server or a TURN server, you should run these separately.
+This Docker image will run Synapse as a single process. By default it uses a
+sqlite database; for production use you should connect it to a separate
+postgres database.
 
-## Run
+The image also does *not* provide a TURN server.
 
-We do not currently offer a `latest` image, as this has somewhat undefined semantics.
-We instead release only tagged versions so upgrading between releases is entirely
-within your control.
+## Run
 
 ### Using docker-compose (easier)
 
-This image is designed to run either with an automatically generated configuration
-file or with a custom configuration that requires manual editing.
+This image is designed to run either with an automatically generated
+configuration file or with a custom configuration that requires manual editing.
 
 An easy way to make use of this image is via docker-compose. See the
-[contrib/docker](../contrib/docker)
-section of the synapse project for examples.
+[contrib/docker](../contrib/docker) section of the synapse project for
+examples.
 
 ### Without Compose (harder)
 
@@ -32,7 +31,7 @@ docker run \
     -v ${DATA_PATH}:/data \
     -e SYNAPSE_SERVER_NAME=my.matrix.host \
     -e SYNAPSE_REPORT_STATS=yes \
-    docker.io/matrixdotorg/synapse:latest
+    matrixdotorg/synapse:latest
 ```
 
 ## Volumes
@@ -53,6 +52,28 @@ In order to setup an application service, simply create an ``appservices``
 directory in the data volume and write the application service Yaml
 configuration file there. Multiple application services are supported.
 
+## TLS certificates
+
+Synapse requires a valid TLS certificate. You can do one of the following:
+
+ * Provide your own certificate and key (as
+   `${DATA_PATH}/${SYNAPSE_SERVER_NAME}.crt` and
+   `${DATA_PATH}/${SYNAPSE_SERVER_NAME}.key`, or elsewhere by providing an
+   entire config as `${SYNAPSE_CONFIG_PATH}`).
+
+ * Use a reverse proxy to terminate incoming TLS, and forward the plain http
+   traffic to port 8008 in the container. In this case you should set `-e
+   SYNAPSE_NO_TLS=1`.
+
+ * Use the ACME (Let's Encrypt) support built into Synapse. This requires
+   `${SYNAPSE_SERVER_NAME}` port 80 to be forwarded to port 8009 in the
+   container, for example with `-p 80:8009`. To enable it in the docker
+   container, set `-e SYNAPSE_ACME=1`.
+
+If you don't do any of these, Synapse will fail to start with an error similar to:
+
+    synapse.config._base.ConfigError: Error accessing file '/data/<server_name>.tls.crt' (config for tls_certificate): No such file or directory
+
 ## Environment
 
 Unless you specify a custom path for the configuration file, a very generic
@@ -71,7 +92,7 @@ then customize it manually. No other environment variable is required.
 Otherwise, a dynamic configuration file will be used. The following environment
 variables are available for configuration:
 
-* ``SYNAPSE_SERVER_NAME`` (mandatory), the current server public hostname.
+* ``SYNAPSE_SERVER_NAME`` (mandatory), the server public hostname.
 * ``SYNAPSE_REPORT_STATS``, (mandatory, ``yes`` or ``no``), enable anonymous
   statistics reporting back to the Matrix project which helps us to get funding.
 * ``SYNAPSE_NO_TLS``, set this variable to disable TLS in Synapse (use this if
@@ -80,7 +101,6 @@ variables are available for configuration:
   the Synapse instance.
 * ``SYNAPSE_ALLOW_GUEST``, set this variable to allow guest joining this server.
 * ``SYNAPSE_EVENT_CACHE_SIZE``, the event cache size [default `10K`].
-* ``SYNAPSE_CACHE_FACTOR``, the cache factor [default `0.5`].
 * ``SYNAPSE_RECAPTCHA_PUBLIC_KEY``, set this variable to the recaptcha public
   key in order to enable recaptcha upon registration.
 * ``SYNAPSE_RECAPTCHA_PRIVATE_KEY``, set this variable to the recaptcha private
@@ -88,7 +108,9 @@ variables are available for configuration:
 * ``SYNAPSE_TURN_URIS``, set this variable to the coma-separated list of TURN
   uris to enable TURN for this homeserver.
 * ``SYNAPSE_TURN_SECRET``, set this to the TURN shared secret if required.
-* ``SYNAPSE_MAX_UPLOAD_SIZE``, set this variable to change the max upload size [default `10M`].
+* ``SYNAPSE_MAX_UPLOAD_SIZE``, set this variable to change the max upload size
+  [default `10M`].
+* ``SYNAPSE_ACME``: set this to enable the ACME certificate renewal support.
 
 Shared secrets, that will be initialized to random values if not set:
 
@@ -99,27 +121,25 @@ Shared secrets, that will be initialized to random values if not set:
 
 Database specific values (will use SQLite if not set):
 
-* `POSTGRES_DB` - The database name for the synapse postgres database. [default: `synapse`]
-* `POSTGRES_HOST` - The host of the postgres database if you wish to use postgresql instead of sqlite3. [default: `db` which is useful when using a container on the same docker network in a compose file where the postgres service is called `db`]
-* `POSTGRES_PASSWORD` - The password for the synapse postgres database. **If this is set then postgres will be used instead of sqlite3.** [default: none] **NOTE**: You are highly encouraged to use postgresql! Please use the compose file to make it easier to deploy.
-* `POSTGRES_USER` - The user for the synapse postgres database. [default: `matrix`]
+* `POSTGRES_DB` - The database name for the synapse postgres
+  database. [default: `synapse`]
+* `POSTGRES_HOST` - The host of the postgres database if you wish to use
+  postgresql instead of sqlite3. [default: `db` which is useful when using a
+  container on the same docker network in a compose file where the postgres
+  service is called `db`]
+* `POSTGRES_PASSWORD` - The password for the synapse postgres database. **If
+  this is set then postgres will be used instead of sqlite3.** [default: none]
+  **NOTE**: You are highly encouraged to use postgresql! Please use the compose
+  file to make it easier to deploy.
+* `POSTGRES_USER` - The user for the synapse postgres database. [default:
+  `matrix`]
 
 Mail server specific values (will not send emails if not set):
 
 * ``SYNAPSE_SMTP_HOST``, hostname to the mail server.
-* ``SYNAPSE_SMTP_PORT``, TCP port for accessing the mail server [default ``25``].
-* ``SYNAPSE_SMTP_USER``, username for authenticating against the mail server if any.
-* ``SYNAPSE_SMTP_PASSWORD``, password for authenticating against the mail server if any.
-
-## Build
-
-Build the docker image with the `docker build` command from the root of the synapse repository.
-
-```
-docker build -t docker.io/matrixdotorg/synapse . -f docker/Dockerfile
-```
-
-The `-t` option sets the image tag. Official images are tagged `matrixdotorg/synapse:<version>` where `<version>` is the same as the release tag in the synapse git repository.
-
-You may have a local Python wheel cache available, in which case copy the relevant
-packages in the ``cache/`` directory at the root of the project.
+* ``SYNAPSE_SMTP_PORT``, TCP port for accessing the mail server [default
+  ``25``].
+* ``SYNAPSE_SMTP_USER``, username for authenticating against the mail server if
+  any.
+* ``SYNAPSE_SMTP_PASSWORD``, password for authenticating against the mail
+  server if any.
diff --git a/docker/build_debian_packages.sh b/docker/build_debian_packages.sh
deleted file mode 100755
index 08c68dd4..00000000
--- a/docker/build_debian_packages.sh
+++ /dev/null
@@ -1,46 +0,0 @@
-#!/bin/bash
-
-# Build the Debian packages using Docker images.
-#
-# This script builds the Docker images and then executes them sequentially, each
-# one building a Debian package for the targeted operating system. It is
-# designed to be a "single command" to produce all the images.
-#
-# By default, builds for all known distributions, but a list of distributions
-# can be passed on the commandline for debugging.
-
-set -ex
-
-cd `dirname $0`
-
-if [ $# -lt 1 ]; then
-    DISTS=(
-        debian:stretch
-        debian:buster
-        debian:sid
-        ubuntu:xenial
-        ubuntu:bionic
-        ubuntu:cosmic
-    )
-else
-    DISTS=("$@")
-fi
-
-# Make the dir where the debs will live.
-#
-# Note that we deliberately put this outside the source tree, otherwise we tend
-# to get source packages which are full of debs. (We could hack around that
-# with more magic in the build_debian.sh script, but that doesn't solve the
-# problem for natively-run dpkg-buildpakage).
-
-mkdir -p ../../debs
-
-# Build each OS image;
-for i in "${DISTS[@]}"; do
-    TAG=$(echo ${i} | cut -d ":" -f 2)
-    docker build --tag dh-venv-builder:${TAG} --build-arg distro=${i} -f Dockerfile-dhvirtualenv .
-    docker run -it --rm --volume=$(pwd)/../\:/synapse/source:ro --volume=$(pwd)/../../debs:/debs \
-           -e TARGET_USERID=$(id -u) \
-           -e TARGET_GROUPID=$(id -g) \
-           dh-venv-builder:${TAG}
-done
diff --git a/docker/conf/dummy.tls.crt b/docker/conf/dummy.tls.crt
new file mode 100644
index 00000000..8e3b1a9a
--- /dev/null
+++ b/docker/conf/dummy.tls.crt
@@ -0,0 +1,17 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
diff --git a/docker/conf/homeserver.yaml b/docker/conf/homeserver.yaml
index c2b8576a..f07d5c10 100644
--- a/docker/conf/homeserver.yaml
+++ b/docker/conf/homeserver.yaml
@@ -2,11 +2,24 @@
 
 ## TLS ##
 
+{% if SYNAPSE_NO_TLS %}
+no_tls: True
+
+# workaround for https://github.com/matrix-org/synapse/issues/4554
+tls_certificate_path: "/conf/dummy.tls.crt"
+
+{% else %}
+
 tls_certificate_path: "/data/{{ SYNAPSE_SERVER_NAME }}.tls.crt"
 tls_private_key_path: "/data/{{ SYNAPSE_SERVER_NAME }}.tls.key"
-tls_dh_params_path: "/data/{{ SYNAPSE_SERVER_NAME }}.tls.dh"
-no_tls: {{ "True" if SYNAPSE_NO_TLS else "False" }}
-tls_fingerprints: []
+
+{% if SYNAPSE_ACME %}
+acme:
+    enabled: true
+    port: 8009
+{% endif %}
+
+{% endif %}
 
 ## Server ##
 
diff --git a/docker/start.py b/docker/start.py
index 346df8c8..941d9996 100755
--- a/docker/start.py
+++ b/docker/start.py
@@ -47,9 +47,8 @@ if mode == "generate":
 
 # In normal mode, generate missing keys if any, then run synapse
 else:
-    # Parse the configuration file
     if "SYNAPSE_CONFIG_PATH" in environ:
-        args += ["--config-path", environ["SYNAPSE_CONFIG_PATH"]]
+        config_path = environ["SYNAPSE_CONFIG_PATH"]
     else:
         check_arguments(environ, ("SYNAPSE_SERVER_NAME", "SYNAPSE_REPORT_STATS"))
         generate_secrets(environ, {
@@ -58,10 +57,21 @@ else:
         })
         environ["SYNAPSE_APPSERVICES"] = glob.glob("/data/appservices/*.yaml")
         if not os.path.exists("/compiled"): os.mkdir("/compiled")
-        convert("/conf/homeserver.yaml", "/compiled/homeserver.yaml", environ)
+
+        config_path = "/compiled/homeserver.yaml"
+
+        convert("/conf/homeserver.yaml", config_path, environ)
         convert("/conf/log.config", "/compiled/log.config", environ)
         subprocess.check_output(["chown", "-R", ownership, "/data"])
-        args += ["--config-path", "/compiled/homeserver.yaml"]
+
+
+    args += [
+        "--config-path", config_path,
+
+        # tell synapse to put any generated keys in /data rather than /compiled
+        "--keys-directory", "/data",
+    ]
+
     # Generate missing keys and start synapse
     subprocess.check_output(args + ["--generate-keys"])
     os.execv("/sbin/su-exec", ["su-exec", ownership] + args)
diff --git a/docs/ACME.md b/docs/ACME.md
new file mode 100644
index 00000000..8fb2bd66
--- /dev/null
+++ b/docs/ACME.md
@@ -0,0 +1,126 @@
+# ACME
+
+Synapse v1.0 will require valid TLS certificates for communication between
+servers (port `8448` by default) in addition to those that are client-facing
+(port `443`). If you do not already have a valid certificate for your domain,
+the easiest way to get one is with Synapse's new ACME support, which will use
+the ACME protocol to provision a certificate automatically. Synapse v0.99.0+
+will provision server-to-server certificates automatically for you for free
+through [Let's Encrypt](https://letsencrypt.org/) if you tell it to.
+
+In the case that your `server_name` config variable is the same as
+the hostname that the client connects to, then the same certificate can be
+used between client and federation ports without issue. 
+
+For a sample configuration, please inspect the new ACME section in the example
+generated config by running the `generate-config` executable. For example:
+
+```
+~/synapse/env3/bin/generate-config
+```
+
+You will need to provide Let's Encrypt (or another ACME provider) access to
+your Synapse ACME challenge responder on port 80, at the domain of your
+homeserver. This requires you to either change the port of the ACME listener
+provided by Synapse to a high port and reverse proxy to it, or use a tool
+like `authbind` to allow Synapse to listen on port 80 without root access.
+(Do not run Synapse with root permissions!) Detailed instructions are
+available under "ACME setup" below.
+
+If you are already using self-signed certificates, you will need to back up
+or delete them (files `example.com.tls.crt` and `example.com.tls.key` in
+Synapse's root directory), Synapse's ACME implementation will not overwrite
+them.
+
+You may wish to use alternate methods such as Certbot to obtain a certificate
+from Let's Encrypt, depending on your server configuration. Of course, if you
+already have a valid certificate for your homeserver's domain, that can be
+placed in Synapse's config directory without the need for any ACME setup.
+
+## ACME setup
+
+The main steps for enabling ACME support in short summary are:
+
+1. Allow Synapse to listen on port 80 with authbind, or forward it from a reverse-proxy.
+1. Set `acme:enabled` to `true` in homeserver.yaml.
+1. Move your old certificates (files `example.com.tls.crt` and `example.com.tls.key` out of the way if they currently exist at the paths specified in `homeserver.yaml`.
+1. Restart Synapse
+
+Detailed instructions for each step are provided below.
+
+### Listening on port 80
+
+In order for Synapse to complete the ACME challenge to provision a
+certificate, it needs access to port 80. Typically listening on port 80 is
+only granted to applications running as root. There are thus two solutions to
+this problem.
+
+#### Using a reverse proxy
+
+A reverse proxy such as Apache or nginx allows a single process (the web
+server) to listen on port 80 and proxy traffic to the appropriate program
+running on your server. It is the recommended method for setting up ACME as
+it allows you to use your existing webserver while also allowing Synapse to
+provision certificates as needed.
+
+For nginx users, add the following line to your existing `server` block:
+
+```
+location /.well-known/acme-challenge {
+    proxy_pass http://localhost:8009/;
+}
+```
+
+For Apache, add the following to your existing webserver config::
+
+```
+ProxyPass /.well-known/acme-challenge http://localhost:8009/.well-known/acme-challenge
+```
+
+Make sure to restart/reload your webserver after making changes.
+
+
+#### Authbind
+
+`authbind` allows a program which does not run as root to bind to
+low-numbered ports in a controlled way. The setup is simpler, but requires a
+webserver not to already be running on port 80. **This includes every time
+Synapse renews a certificate**, which may be cumbersome if you usually run a
+web server on port 80. Nevertheless, if you're sure port 80 is not being used
+for any other purpose then all that is necessary is the following:
+
+Install `authbind`. For example, on Debian/Ubuntu:
+
+```
+sudo apt-get install authbind
+```
+
+Allow `authbind` to bind port 80:
+
+```
+sudo touch /etc/authbind/byport/80
+sudo chmod 777 /etc/authbind/byport/80
+```
+
+When Synapse is started, use the following syntax::
+
+```
+authbind --deep <synapse start command>
+```
+
+### Config file editing
+
+Once Synapse is able to listen on port 80 for ACME challenge
+requests, it must be told to perform ACME provisioning by setting `enabled`
+to true under the `acme` section in `homeserver.yaml`:
+
+```
+acme:
+    enabled: true
+```
+
+### Starting synapse
+
+Ensure that the certificate paths specified in `homeserver.yaml` (`tls_certificate_path` and `tls_private_key_path`) do not currently point to any files. Synapse will not provision certificates if files exist, as it does not want to overwrite existing certificates.
+
+Finally, start/restart Synapse.
\ No newline at end of file
diff --git a/docs/MSC1711_certificates_FAQ.md b/docs/MSC1711_certificates_FAQ.md
new file mode 100644
index 00000000..efe63306
--- /dev/null
+++ b/docs/MSC1711_certificates_FAQ.md
@@ -0,0 +1,336 @@
+# MSC 1711 Certificates FAQ
+
+The goal of Synapse 0.99.0 is to act as a stepping stone to Synapse 1.0.0. It
+supports the r0.1 release of the server to server specification, but is
+compatible with both the legacy Matrix federation behaviour (pre-r0.1) as well
+as post-r0.1 behaviour, in order to allow for a smooth upgrade across the
+federation.
+
+The most important thing to know is that Synapse 1.0.0 will require a valid TLS
+certificate on federation endpoints. Self signed certificates will not be
+sufficient.
+
+Synapse 0.99.0 makes it easy to configure TLS certificates and will
+interoperate with both >= 1.0.0 servers as well as existing servers yet to
+upgrade.
+
+**It is critical that all admins upgrade to 0.99.0 and configure a valid TLS
+certificate.** Admins will have 1 month to do so, after which 1.0.0 will be
+released and those servers without a valid certificate will not longer be able
+to federate with >= 1.0.0 servers.
+
+Full details on how to carry out this configuration change is given
+[below](#configuring-certificates-for-compatibility-with-synapse-100). A
+timeline and some frequently asked questions are also given below.
+
+For more details and context on the release of the r0.1 Server/Server API and
+imminent Matrix 1.0 release, you can also see our
+[main talk from FOSDEM 2019](https://matrix.org/blog/2019/02/04/matrix-at-fosdem-2019/).
+
+## Contents
+* Timeline
+* Configuring certificates for compatibility with Synapse 1.0
+* FAQ
+  * Synapse 0.99.0 has just been released, what do I need to do right now?
+  * How do I upgrade?
+  * What will happen if I do not set up a valid federation certificate
+    immediately?
+  * What will happen if I do nothing at all?
+  * When do I need a SRV record or .well-known URI?
+  * Can I still use an SRV record?
+  * I have created a .well-known URI. Do I still need an SRV record?
+  * It used to work just fine, why are you breaking everything?
+  * Can I manage my own certificates rather than having Synapse renew
+    certificates itself?
+  * Do you still recommend against using a reverse-proxy on the federation port?
+  * Do I still need to give my TLS certificates to Synapse if I am using a
+    reverse-proxy?
+  * Do I need the same certificate for the client and federation port?
+  * How do I tell Synapse to reload my keys/certificates after I replace them?
+
+## Timeline
+
+**5th Feb 2019  - Synapse 0.99.0 is released.**
+
+All server admins are encouraged to upgrade.
+
+0.99.0:
+
+-   provides support for ACME to make setting up Let's Encrypt certs easy, as
+    well as .well-known support.
+
+-   does not enforce that a valid CA cert is present on the federation API, but
+    rather makes it easy to set one up.
+
+-   provides support for .well-known
+
+Admins should upgrade and configure a valid CA cert. Homeservers that require a
+.well-known entry (see below), should retain their SRV record and use it
+alongside their .well-known record.
+
+**>= 5th March 2019  - Synapse 1.0.0 is released**
+
+1.0.0 will land no sooner than 1 month after 0.99.0, leaving server admins one
+month after 5th February to upgrade to 0.99.0 and deploy their certificates. In
+accordance with the the [S2S spec](https://matrix.org/docs/spec/server_server/r0.1.0.html)
+1.0.0 will enforce certificate validity. This means that any homeserver without a
+valid certificate after this point will no longer be able to federate with
+1.0.0 servers.
+
+
+## Configuring certificates for compatibility with Synapse 1.0.0
+
+### If you do not currently have an SRV record
+
+In this case, your `server_name` points to the host where your Synapse is
+running. There is no need to create a `.well-known` URI or an SRV record, but
+you will need to give Synapse a valid, signed, certificate.
+
+The easiest way to do that is with Synapse's built-in ACME (Let's Encrypt)
+support. Full details are in [ACME.md](./ACME.md) but, in a nutshell:
+
+ 1. Allow Synapse to listen on port 80 with `authbind`, or forward it from a
+    reverse proxy.
+ 2. Enable acme support in `homeserver.yaml`.
+ 3. Move your old certificates out of the way.
+ 4. Restart Synapse.
+
+### If you do have an SRV record currently
+
+If you are using an SRV record, your matrix domain (`server_name`) may not
+point to the same host that your Synapse is running on (the 'target
+domain'). (If it does, you can follow the recommendation above; otherwise, read
+on.)
+
+Let's assume that your `server_name` is `example.com`, and your Synapse is
+hosted at a target domain of `customer.example.net`. Currently you should have
+an SRV record which looks like:
+
+```
+_matrix._tcp.example.com. IN SRV 10 5 443 customer.example.net.
+```
+
+In this situation, you have two choices for how to proceed:
+
+#### Option 1: give Synapse a certificate for your matrix domain
+
+Synapse 1.0 will expect your server to present a TLS certificate for your
+`server_name` (`example.com` in the above example). You can achieve this by
+doing one of the following:
+
+ * Acquire a certificate for the `server_name` yourself (for example, using
+   `certbot`), and give it and the key to Synapse via `tls_certificate_path`
+   and `tls_private_key_path`, or:
+
+ * Use Synapse's [ACME support](./ACME.md), and forward port 80 on the
+   `server_name` domain to your Synapse instance, or:
+
+ * Set up a reverse-proxy on port 8448 on the `server_name` domain, which
+   forwards to Synapse. Once it is set up, you can remove the SRV record.
+
+#### Option 2: add a .well-known file to delegate your matrix traffic
+
+This will allow you to keep Synapse on a separate domain, without having to
+give it a certificate for the matrix domain.
+
+You can do this with a `.well-known` file as follows:
+
+ 1. Keep the SRV record in place - it is needed for backwards compatibility
+    with Synapse 0.34 and earlier.
+
+ 2. Give synapse a certificate corresponding to the target domain
+    (`customer.example.net` in the above example). Currently Synapse's ACME
+    support [does not support
+    this](https://github.com/matrix-org/synapse/issues/4552), so you will have
+    to acquire a certificate yourself and give it to Synapse via
+    `tls_certificate_path` and `tls_private_key_path`.
+
+ 3. Restart Synapse to ensure the new certificate is loaded.
+
+ 4. Arrange for a `.well-known` file at
+    `https://<server_name>/.well-known/matrix/server` with contents:
+
+    ```json
+    {"m.server": "<target domain>:<port>"}
+    ```
+
+    In the above example, `https://example.com/.well-known/matrix/server`
+    should have the contents:
+
+    ```json
+	{"m.server": "customer.example.net:443"}
+    ```
+
+## FAQ
+
+### Synapse 0.99.0 has just been released, what do I need to do right now?
+
+Upgrade as soon as you can in preparation for Synapse 1.0.0.
+
+### How do I upgrade?
+
+Follow the upgrade notes here [UPGRADE.rst](https://github.com/matrix-org/synapse/blob/master/UPGRADE.rst)
+
+### What will happen if I do not set up a valid federation certificate immediately?
+
+Nothing initially, but once 1.0.0 is in the wild it will not be possible to
+federate with 1.0.0 servers.
+
+### What will happen if I do nothing at all?
+
+If the admin takes no action at all, and remains on a Synapse < 0.99.0 then the
+homeserver will be unable to federate with those who have implemented
+.well-known. Then, as above, once the month upgrade window has expired the
+homeserver will not be able to federate with any Synapse >= 1.0.0
+
+### When do I need a SRV record or .well-known URI?
+
+If your homeserver listens on the default federation port (8448), and your
+server_name points to the host that your homeserver runs on, you do not need an
+SRV record or .well-known/matrix/server URI.\
+For instance, if you registered example.com and pointed its DNS A record at a
+fresh Upcloud VPS or similar, you could install Synapse 0.99 on that host,
+giving it a server_name of example.com, and it would automatically generate a
+valid TLS certificate for you via Let's Encrypt and no SRV record or
+.well-known URI would be needed.
+
+This is the common case, although you can add an SRV record or
+.well-known/matrix/server URI for completeness if you wish.
+
+**However**, if your server does not listen on port 8448, or if your server_name
+does not point to the host that your homeserver runs on, you will need to let
+other servers know how to find it.
+
+The easiest way to do this is with a .well-known/matrix/server URI on the
+webroot of the domain to advertise your server. For instance, if you ran
+"matrixhosting.com" and you were hosting a Matrix server for `example.com`, you
+would ask `example.com` to create a file at
+`https://example.com/.well-known/matrix/server` with contents:
+
+```json
+{"m.server": "example.matrixhosting.com:8448"}
+```
+
+...which would tell servers trying to connect to example.com to instead connect
+to example.matrixhosting.com on port 8448. You would then configure Synapse
+with a server_name of "example.com", but generate a TLS certificate for
+example.matrixhosting.com.
+
+As an alternative, you can still use an SRV DNS record for the delegation, but
+this will require you to have a certificate for the matrix domain (example.com
+in this example). See "Can I still use an SRV record?".
+
+### Can I still use an SRV record?
+
+Firstly, if you didn't need an SRV record before (because your server is
+listening on port 8448 of your server_name), you certainly don't need one now:
+the defaults are still the same.
+
+If you previously had an SRV record, you can keep using it provided you are
+able to give Synapse a TLS certificate corresponding to your server name. For
+example, suppose you had the following SRV record, which directs matrix traffic
+for example.com to matrix.example.com:443:
+
+```
+_matrix._tcp.example.com. IN SRV 10 5 443 matrix.example.com
+```
+
+In this case, Synapse must be given a certificate for example.com - or be
+configured to acquire one from Let's Encrypt.
+
+If you are unable to give Synapse a certificate for your server_name, you will
+also need to use a .well-known URI instead. However, see also "I have created a
+.well-known URI. Do I still need an SRV record?".
+
+### I have created a .well-known URI. Do I still need an SRV record?
+
+As of Synapse 0.99, Synapse will first check for the existence of a .well-known
+URL and follow any delegation it suggests. It will only then check for the
+existence of an SRV record.
+
+That means that the SRV record will often be redundant. However, you should
+remember that there may still be older versions of Synapse in the federation
+which do not understand .well-known URIs, so if you removed your SRV record you
+would no longer be able to federate with them.
+
+It is therefore best to leave the SRV record in place for now. Synapse 0.34 and
+earlier will follow the SRV record (and not care about the invalid
+certificate). Synapse 0.99 and later will follow the .well-known URI, with the
+correct certificate chain.
+
+### It used to work just fine, why are you breaking everything?
+
+We have always wanted Matrix servers to be as easy to set up as possible, and
+so back when we started federation in 2014 we didn't want admins to have to go
+through the cumbersome process of buying a valid TLS certificate to run a
+server. This was before Let's Encrypt came along and made getting a free and
+valid TLS certificate straightforward. So instead, we adopted a system based on
+[Perspectives](https://en.wikipedia.org/wiki/Convergence_(SSL)): an approach
+where you check a set of "notary servers" (in practice, homeservers) to vouch
+for the validity of a certificate rather than having it signed by a CA. As long
+as enough different notaries agree on the certificate's validity, then it is
+trusted.
+
+However, in practice this has never worked properly. Most people only use the
+default notary server (matrix.org), leading to inadvertent centralisation which
+we want to eliminate. Meanwhile, we never implemented the full consensus
+algorithm to query the servers participating in a room to determine consensus
+on whether a given certificate is valid. This is fiddly to get right
+(especially in face of sybil attacks), and we found ourselves questioning
+whether it was worth the effort to finish the work and commit to maintaining a
+secure certificate validation system as opposed to focusing on core Matrix
+development.
+
+Meanwhile, Let's Encrypt came along in 2016, and put the final nail in the
+coffin of the Perspectives project (which was already pretty dead). So, the
+Spec Core Team decided that a better approach would be to mandate valid TLS
+certificates for federation alongside the rest of the Web. More details can be
+found in
+[MSC1711](https://github.com/matrix-org/matrix-doc/blob/master/proposals/1711-x509-for-federation.md#background-the-failure-of-the-perspectives-approach).
+
+This results in a breaking change, which is disruptive, but absolutely critical
+for the security model. However, the existence of Let's Encrypt as a trivial
+way to replace the old self-signed certificates with valid CA-signed ones helps
+smooth things over massively, especially as Synapse can now automate Let's
+Encrypt certificate generation if needed.
+
+### Can I manage my own certificates rather than having Synapse renew certificates itself?
+
+Yes, you are welcome to manage your certificates yourself. Synapse will only
+attempt to obtain certificates from Let's Encrypt if you configure it to do
+so.The only requirement is that there is a valid TLS cert present for
+federation end points.
+
+### Do you still recommend against using a reverse-proxy on the federation port?
+
+We no longer actively recommend against using a reverse proxy. Many admins will
+find it easier to direct federation traffic to a reverse-proxy and manage their
+own TLS certificates, and this is a supported configuration.
+
+### Do I still need to give my TLS certificates to Synapse if I am using a reverse proxy?
+
+Practically speaking, this is no longer necessary.
+
+If you are using a reverse-proxy for all of your TLS traffic, then you can set
+`no_tls: True`. In that case, the only reason Synapse needs the certificate is
+to populate a legacy 'tls_fingerprints' field in the federation API. This is
+ignored by Synapse 0.99.0 and later, and the only time pre-0.99 Synapses will
+check it is when attempting to fetch the server keys - and generally this is
+delegated via `matrix.org`, which is on 0.99.0.
+
+However, there is a bug in Synapse 0.99.0
+[4554](<https://github.com/matrix-org/synapse/issues/4554>) which prevents
+Synapse from starting if you do not give it a TLS certificate. To work around
+this, you can give it any TLS certificate at all. This will be fixed soon.
+
+### Do I need the same certificate for the client and federation port?
+
+No. There is nothing stopping you doing so, particularly if you are using a
+reverse-proxy. However, Synapse will use the same certificate on any ports
+where TLS is configured.
+
+### How do I tell Synapse to reload my keys/certificates after I replace them?
+
+Synapse will reload the keys and certificates when it receives a SIGHUP - for
+example kill -HUP $(cat homeserver.pid). Alternatively, simply restart Synapse,
+though this will result in downtime while it restarts.
diff --git a/scripts-dev/build_debian_packages b/scripts-dev/build_debian_packages
new file mode 100755
index 00000000..6b9be990
--- /dev/null
+++ b/scripts-dev/build_debian_packages
@@ -0,0 +1,154 @@
+#!/usr/bin/env python3
+
+# Build the Debian packages using Docker images.
+#
+# This script builds the Docker images and then executes them sequentially, each
+# one building a Debian package for the targeted operating system. It is
+# designed to be a "single command" to produce all the images.
+#
+# By default, builds for all known distributions, but a list of distributions
+# can be passed on the commandline for debugging.
+
+import argparse
+import os
+import signal
+import subprocess
+import sys
+import threading
+from concurrent.futures import ThreadPoolExecutor
+
+DISTS = (
+    "debian:stretch",
+    "debian:buster",
+    "debian:sid",
+    "ubuntu:xenial",
+    "ubuntu:bionic",
+    "ubuntu:cosmic",
+)
+
+DESC = '''\
+Builds .debs for synapse, using a Docker image for the build environment.
+
+By default, builds for all known distributions, but a list of distributions
+can be passed on the commandline for debugging.
+'''
+
+
+class Builder(object):
+    def __init__(self, redirect_stdout=False):
+        self.redirect_stdout = redirect_stdout
+        self.active_containers = set()
+        self._lock = threading.Lock()
+        self._failed = False
+
+    def run_build(self, dist):
+        """Build deb for a single distribution"""
+
+        if self._failed:
+            print("not building %s due to earlier failure" % (dist, ))
+            raise Exception("failed")
+
+        try:
+            self._inner_build(dist)
+        except Exception as e:
+            print("build of %s failed: %s" % (dist, e), file=sys.stderr)
+            self._failed = True
+            raise
+
+    def _inner_build(self, dist):
+        projdir = os.path.dirname(os.path.dirname(os.path.realpath(__file__)))
+        os.chdir(projdir)
+
+        tag = dist.split(":", 1)[1]
+
+        # Make the dir where the debs will live.
+        #
+        # Note that we deliberately put this outside the source tree, otherwise
+        # we tend to get source packages which are full of debs. (We could hack
+        # around that with more magic in the build_debian.sh script, but that
+        # doesn't solve the problem for natively-run dpkg-buildpakage).
+        debsdir = os.path.join(projdir, '../debs')
+        os.makedirs(debsdir, exist_ok=True)
+
+        if self.redirect_stdout:
+            logfile = os.path.join(debsdir, "%s.buildlog" % (tag, ))
+            print("building %s: directing output to %s" % (dist, logfile))
+            stdout = open(logfile, "w")
+        else:
+            stdout = None
+
+        # first build a docker image for the build environment
+        subprocess.check_call([
+            "docker", "build",
+            "--tag", "dh-venv-builder:" + tag,
+            "--build-arg", "distro=" + dist,
+            "-f", "docker/Dockerfile-dhvirtualenv",
+            "docker",
+        ], stdout=stdout, stderr=subprocess.STDOUT)
+
+        container_name = "synapse_build_" + tag
+        with self._lock:
+            self.active_containers.add(container_name)
+
+        # then run the build itself
+        subprocess.check_call([
+            "docker", "run",
+            "--rm",
+            "--name", container_name,
+            "--volume=" + projdir + ":/synapse/source:ro",
+            "--volume=" + debsdir + ":/debs",
+            "-e", "TARGET_USERID=%i" % (os.getuid(), ),
+            "-e", "TARGET_GROUPID=%i" % (os.getgid(), ),
+            "dh-venv-builder:" + tag,
+        ], stdout=stdout, stderr=subprocess.STDOUT)
+
+        with self._lock:
+            self.active_containers.remove(container_name)
+
+        if stdout is not None:
+            stdout.close()
+            print("Completed build of %s" % (dist, ))
+
+    def kill_containers(self):
+        with self._lock:
+            active = list(self.active_containers)
+
+        for c in active:
+            print("killing container %s" % (c,))
+            subprocess.run([
+                "docker", "kill", c,
+            ], stdout=subprocess.DEVNULL)
+            with self._lock:
+                self.active_containers.remove(c)
+
+
+def run_builds(dists, jobs=1):
+    builder = Builder(redirect_stdout=(jobs > 1))
+
+    def sig(signum, _frame):
+        print("Caught SIGINT")
+        builder.kill_containers()
+    signal.signal(signal.SIGINT, sig)
+
+    with ThreadPoolExecutor(max_workers=jobs) as e:
+        res = e.map(builder.run_build, dists)
+
+    # make sure we consume the iterable so that exceptions are raised.
+    for r in res:
+        pass
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(
+        description=DESC,
+    )
+    parser.add_argument(
+        '-j', '--jobs', type=int, default=1,
+        help='specify the number of builds to run in parallel',
+    )
+    parser.add_argument(
+        'dist', nargs='*', default=DISTS,
+        help='a list of distributions to build for. Default: %(default)s',
+    )
+    args = parser.parse_args()
+    run_builds(dists=args.dist, jobs=args.jobs)
diff --git a/synapse/__init__.py b/synapse/__init__.py
index d6a191cc..048d6e57 100644
--- a/synapse/__init__.py
+++ b/synapse/__init__.py
@@ -27,4 +27,4 @@ try:
 except ImportError:
     pass
 
-__version__ = "0.34.1.1"
+__version__ = "0.99.0"
diff --git a/synapse/_scripts/register_new_matrix_user.py b/synapse/_scripts/register_new_matrix_user.py
index 4c3abf06..6e93f5a0 100644
--- a/synapse/_scripts/register_new_matrix_user.py
+++ b/synapse/_scripts/register_new_matrix_user.py
@@ -46,7 +46,7 @@ def request_registration(
     # Get the nonce
     r = requests.get(url, verify=False)
 
-    if r.status_code is not 200:
+    if r.status_code != 200:
         _print("ERROR! Received %d %s" % (r.status_code, r.reason))
         if 400 <= r.status_code < 500:
             try:
@@ -84,7 +84,7 @@ def request_registration(
     _print("Sending registration request...")
     r = requests.post(url, json=data, verify=False)
 
-    if r.status_code is not 200:
+    if r.status_code != 200:
         _print("ERROR! Received %d %s" % (r.status_code, r.reason))
         if 400 <= r.status_code < 500:
             try:
diff --git a/synapse/api/auth.py b/synapse/api/auth.py
index ba1019b9..5992d306 100644
--- a/synapse/api/auth.py
+++ b/synapse/api/auth.py
@@ -65,7 +65,7 @@ class Auth(object):
         register_cache("cache", "token_cache", self.token_cache)
 
     @defer.inlineCallbacks
-    def check_from_context(self, event, context, do_sig_check=True):
+    def check_from_context(self, room_version, event, context, do_sig_check=True):
         prev_state_ids = yield context.get_prev_state_ids(self.store)
         auth_events_ids = yield self.compute_auth_events(
             event, prev_state_ids, for_verification=True,
@@ -74,12 +74,16 @@ class Auth(object):
         auth_events = {
             (e.type, e.state_key): e for e in itervalues(auth_events)
         }
-        self.check(event, auth_events=auth_events, do_sig_check=do_sig_check)
+        self.check(
+            room_version, event,
+            auth_events=auth_events, do_sig_check=do_sig_check,
+        )
 
-    def check(self, event, auth_events, do_sig_check=True):
+    def check(self, room_version, event, auth_events, do_sig_check=True):
         """ Checks if this event is correctly authed.
 
         Args:
+            room_version (str): version of the room
             event: the event being checked.
             auth_events (dict: event-key -> event): the existing room state.
 
@@ -88,7 +92,9 @@ class Auth(object):
             True if the auth checks pass.
         """
         with Measure(self.clock, "auth.check"):
-            event_auth.check(event, auth_events, do_sig_check=do_sig_check)
+            event_auth.check(
+                room_version, event, auth_events, do_sig_check=do_sig_check
+            )
 
     @defer.inlineCallbacks
     def check_joined_room(self, room_id, user_id, current_state=None):
@@ -545,17 +551,6 @@ class Auth(object):
         return self.store.is_server_admin(user)
 
     @defer.inlineCallbacks
-    def add_auth_events(self, builder, context):
-        prev_state_ids = yield context.get_prev_state_ids(self.store)
-        auth_ids = yield self.compute_auth_events(builder, prev_state_ids)
-
-        auth_events_entries = yield self.store.add_event_hashes(
-            auth_ids
-        )
-
-        builder.auth_events = auth_events_entries
-
-    @defer.inlineCallbacks
     def compute_auth_events(self, event, current_state_ids, for_verification=False):
         if event.type == EventTypes.Create:
             defer.returnValue([])
@@ -571,7 +566,7 @@ class Auth(object):
         key = (EventTypes.JoinRules, "", )
         join_rule_event_id = current_state_ids.get(key)
 
-        key = (EventTypes.Member, event.user_id, )
+        key = (EventTypes.Member, event.sender, )
         member_event_id = current_state_ids.get(key)
 
         key = (EventTypes.Create, "", )
@@ -621,7 +616,7 @@ class Auth(object):
 
         defer.returnValue(auth_ids)
 
-    def check_redaction(self, event, auth_events):
+    def check_redaction(self, room_version, event, auth_events):
         """Check whether the event sender is allowed to redact the target event.
 
         Returns:
@@ -634,7 +629,7 @@ class Auth(object):
             AuthError if the event sender is definitely not allowed to redact
             the target event.
         """
-        return event_auth.check_redaction(event, auth_events)
+        return event_auth.check_redaction(room_version, event, auth_events)
 
     @defer.inlineCallbacks
     def check_can_change_room_list(self, room_id, user):
@@ -819,7 +814,9 @@ class Auth(object):
             elif threepid:
                 # If the user does not exist yet, but is signing up with a
                 # reserved threepid then pass auth check
-                if is_threepid_reserved(self.hs.config, threepid):
+                if is_threepid_reserved(
+                    self.hs.config.mau_limits_reserved_threepids, threepid
+                ):
                     return
             # Else if there is no room in the MAU bucket, bail
             current_mau = yield self.store.get_monthly_active_count()
diff --git a/synapse/api/constants.py b/synapse/api/constants.py
index 87bc1cb5..fedfb92b 100644
--- a/synapse/api/constants.py
+++ b/synapse/api/constants.py
@@ -68,6 +68,7 @@ class EventTypes(object):
     Aliases = "m.room.aliases"
     Redaction = "m.room.redaction"
     ThirdPartyInvite = "m.room.third_party_invite"
+    Encryption = "m.room.encryption"
 
     RoomHistoryVisibility = "m.room.history_visibility"
     CanonicalAlias = "m.room.canonical_alias"
@@ -103,10 +104,15 @@ class ThirdPartyEntityKind(object):
 class RoomVersions(object):
     V1 = "1"
     V2 = "2"
-    VDH_TEST = "vdh-test-version"
+    V3 = "3"
     STATE_V2_TEST = "state-v2-test"
 
 
+class RoomDisposition(object):
+    STABLE = "stable"
+    UNSTABLE = "unstable"
+
+
 # the version we will give rooms which are created on this server
 DEFAULT_ROOM_VERSION = RoomVersions.V1
 
@@ -115,10 +121,26 @@ DEFAULT_ROOM_VERSION = RoomVersions.V1
 KNOWN_ROOM_VERSIONS = {
     RoomVersions.V1,
     RoomVersions.V2,
-    RoomVersions.VDH_TEST,
+    RoomVersions.V3,
     RoomVersions.STATE_V2_TEST,
+    RoomVersions.V3,
 }
 
+
+class EventFormatVersions(object):
+    """This is an internal enum for tracking the version of the event format,
+    independently from the room version.
+    """
+    V1 = 1
+    V2 = 2
+
+
+KNOWN_EVENT_FORMAT_VERSIONS = {
+    EventFormatVersions.V1,
+    EventFormatVersions.V2,
+}
+
+
 ServerNoticeMsgType = "m.server_notice"
 ServerNoticeLimitReached = "m.server_notice.usage_limit_reached"
 
@@ -128,4 +150,4 @@ class UserTypes(object):
     'admin' and 'guest' users should also be UserTypes. Normal users are type None
     """
     SUPPORT = "support"
-    ALL_USER_TYPES = (SUPPORT)
+    ALL_USER_TYPES = (SUPPORT,)
diff --git a/synapse/api/filtering.py b/synapse/api/filtering.py
index 16ad6548..39064754 100644
--- a/synapse/api/filtering.py
+++ b/synapse/api/filtering.py
@@ -444,6 +444,20 @@ class Filter(object):
     def include_redundant_members(self):
         return self.filter_json.get("include_redundant_members", False)
 
+    def with_room_ids(self, room_ids):
+        """Returns a new filter with the given room IDs appended.
+
+        Args:
+            room_ids (iterable[unicode]): The room_ids to add
+
+        Returns:
+            filter: A new filter including the given rooms and the old
+                    filter's rooms.
+        """
+        newFilter = Filter(self.filter_json)
+        newFilter.rooms += room_ids
+        return newFilter
+
 
 def _matches_wildcard(actual_value, filter_value):
     if filter_value.endswith("*"):
diff --git a/synapse/api/urls.py b/synapse/api/urls.py
index f78695b6..81021766 100644
--- a/synapse/api/urls.py
+++ b/synapse/api/urls.py
@@ -24,7 +24,9 @@ from synapse.config import ConfigError
 
 CLIENT_PREFIX = "/_matrix/client/api/v1"
 CLIENT_V2_ALPHA_PREFIX = "/_matrix/client/v2_alpha"
-FEDERATION_PREFIX = "/_matrix/federation/v1"
+FEDERATION_PREFIX = "/_matrix/federation"
+FEDERATION_V1_PREFIX = FEDERATION_PREFIX + "/v1"
+FEDERATION_V2_PREFIX = FEDERATION_PREFIX + "/v2"
 STATIC_PREFIX = "/_matrix/static"
 WEB_CLIENT_PREFIX = "/_matrix/client"
 CONTENT_REPO_PREFIX = "/_matrix/content"
diff --git a/synapse/app/__init__.py b/synapse/app/__init__.py
index b45adafd..f56f5fcc 100644
--- a/synapse/app/__init__.py
+++ b/synapse/app/__init__.py
@@ -12,15 +12,38 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-
+import logging
 import sys
 
 from synapse import python_dependencies  # noqa: E402
 
 sys.dont_write_bytecode = True
 
+logger = logging.getLogger(__name__)
+
 try:
     python_dependencies.check_requirements()
 except python_dependencies.DependencyException as e:
     sys.stderr.writelines(e.message)
     sys.exit(1)
+
+
+def check_bind_error(e, address, bind_addresses):
+    """
+    This method checks an exception occurred while binding on 0.0.0.0.
+    If :: is specified in the bind addresses a warning is shown.
+    The exception is still raised otherwise.
+
+    Binding on both 0.0.0.0 and :: causes an exception on Linux and macOS
+    because :: binds on both IPv4 and IPv6 (as per RFC 3493).
+    When binding on 0.0.0.0 after :: this can safely be ignored.
+
+    Args:
+        e (Exception): Exception that was caught.
+        address (str): Address on which binding was attempted.
+        bind_addresses (list): Addresses on which the service listens.
+    """
+    if address == '0.0.0.0' and '::' in bind_addresses:
+        logger.warn('Failed to listen on 0.0.0.0, continuing because listening on [::]')
+    else:
+        raise e
diff --git a/synapse/app/_base.py b/synapse/app/_base.py
index 18584226..5b97a54d 100644
--- a/synapse/app/_base.py
+++ b/synapse/app/_base.py
@@ -22,6 +22,7 @@ from daemonize import Daemonize
 
 from twisted.internet import error, reactor
 
+from synapse.app import check_bind_error
 from synapse.util import PreserveLoggingContext
 from synapse.util.rlimit import change_resource_limit
 
@@ -143,6 +144,9 @@ def listen_metrics(bind_addresses, port):
 def listen_tcp(bind_addresses, port, factory, reactor=reactor, backlog=50):
     """
     Create a TCP socket for a port and several addresses
+
+    Returns:
+        list (empty)
     """
     for address in bind_addresses:
         try:
@@ -155,42 +159,33 @@ def listen_tcp(bind_addresses, port, factory, reactor=reactor, backlog=50):
         except error.CannotListenError as e:
             check_bind_error(e, address, bind_addresses)
 
+    logger.info("Synapse now listening on TCP port %d", port)
+    return []
+
 
 def listen_ssl(
     bind_addresses, port, factory, context_factory, reactor=reactor, backlog=50
 ):
     """
-    Create an SSL socket for a port and several addresses
+    Create an TLS-over-TCP socket for a port and several addresses
+
+    Returns:
+        list of twisted.internet.tcp.Port listening for TLS connections
     """
+    r = []
     for address in bind_addresses:
         try:
-            reactor.listenSSL(
-                port,
-                factory,
-                context_factory,
-                backlog,
-                address
+            r.append(
+                reactor.listenSSL(
+                    port,
+                    factory,
+                    context_factory,
+                    backlog,
+                    address
+                )
             )
         except error.CannotListenError as e:
             check_bind_error(e, address, bind_addresses)
 
-
-def check_bind_error(e, address, bind_addresses):
-    """
-    This method checks an exception occurred while binding on 0.0.0.0.
-    If :: is specified in the bind addresses a warning is shown.
-    The exception is still raised otherwise.
-
-    Binding on both 0.0.0.0 and :: causes an exception on Linux and macOS
-    because :: binds on both IPv4 and IPv6 (as per RFC 3493).
-    When binding on 0.0.0.0 after :: this can safely be ignored.
-
-    Args:
-        e (Exception): Exception that was caught.
-        address (str): Address on which binding was attempted.
-        bind_addresses (list): Addresses on which the service listens.
-    """
-    if address == '0.0.0.0' and '::' in bind_addresses:
-        logger.warn('Failed to listen on 0.0.0.0, continuing because listening on [::]')
-    else:
-        raise e
+    logger.info("Synapse now listening on port %d (TLS)", port)
+    return r
diff --git a/synapse/app/client_reader.py b/synapse/app/client_reader.py
index 76aed8c6..f8a417cb 100644
--- a/synapse/app/client_reader.py
+++ b/synapse/app/client_reader.py
@@ -164,23 +164,23 @@ def start(config_options):
 
     database_engine = create_engine(config.database_config)
 
-    tls_server_context_factory = context_factory.ServerContextFactory(config)
-    tls_client_options_factory = context_factory.ClientTLSOptionsFactory(config)
-
     ss = ClientReaderServer(
         config.server_name,
         db_config=config.database_config,
-        tls_server_context_factory=tls_server_context_factory,
-        tls_client_options_factory=tls_client_options_factory,
         config=config,
         version_string="Synapse/" + get_version_string(synapse),
         database_engine=database_engine,
     )
 
     ss.setup()
-    ss.start_listening(config.worker_listeners)
 
     def start():
+        ss.config.read_certificate_from_disk()
+        ss.tls_server_context_factory = context_factory.ServerContextFactory(config)
+        ss.tls_client_options_factory = context_factory.ClientTLSOptionsFactory(
+            config
+        )
+        ss.start_listening(config.worker_listeners)
         ss.get_datastore().start_profiling()
 
     reactor.callWhenRunning(start)
diff --git a/synapse/app/event_creator.py b/synapse/app/event_creator.py
index e4a68715..656e0edc 100644
--- a/synapse/app/event_creator.py
+++ b/synapse/app/event_creator.py
@@ -185,23 +185,23 @@ def start(config_options):
 
     database_engine = create_engine(config.database_config)
 
-    tls_server_context_factory = context_factory.ServerContextFactory(config)
-    tls_client_options_factory = context_factory.ClientTLSOptionsFactory(config)
-
     ss = EventCreatorServer(
         config.server_name,
         db_config=config.database_config,
-        tls_server_context_factory=tls_server_context_factory,
-        tls_client_options_factory=tls_client_options_factory,
         config=config,
         version_string="Synapse/" + get_version_string(synapse),
         database_engine=database_engine,
     )
 
     ss.setup()
-    ss.start_listening(config.worker_listeners)
 
     def start():
+        ss.config.read_certificate_from_disk()
+        ss.tls_server_context_factory = context_factory.ServerContextFactory(config)
+        ss.tls_client_options_factory = context_factory.ClientTLSOptionsFactory(
+            config
+        )
+        ss.start_listening(config.worker_listeners)
         ss.get_datastore().start_profiling()
 
     reactor.callWhenRunning(start)
diff --git a/synapse/app/federation_reader.py b/synapse/app/federation_reader.py
index 228a297f..3de27151 100644
--- a/synapse/app/federation_reader.py
+++ b/synapse/app/federation_reader.py
@@ -151,23 +151,23 @@ def start(config_options):
 
     database_engine = create_engine(config.database_config)
 
-    tls_server_context_factory = context_factory.ServerContextFactory(config)
-    tls_client_options_factory = context_factory.ClientTLSOptionsFactory(config)
-
     ss = FederationReaderServer(
         config.server_name,
         db_config=config.database_config,
-        tls_server_context_factory=tls_server_context_factory,
-        tls_client_options_factory=tls_client_options_factory,
         config=config,
         version_string="Synapse/" + get_version_string(synapse),
         database_engine=database_engine,
     )
 
     ss.setup()
-    ss.start_listening(config.worker_listeners)
 
     def start():
+        ss.config.read_certificate_from_disk()
+        ss.tls_server_context_factory = context_factory.ServerContextFactory(config)
+        ss.tls_client_options_factory = context_factory.ClientTLSOptionsFactory(
+            config
+        )
+        ss.start_listening(config.worker_listeners)
         ss.get_datastore().start_profiling()
 
     reactor.callWhenRunning(start)
diff --git a/synapse/app/federation_sender.py b/synapse/app/federation_sender.py
index e9a99d76..d944e051 100644
--- a/synapse/app/federation_sender.py
+++ b/synapse/app/federation_sender.py
@@ -183,24 +183,24 @@ def start(config_options):
     # Force the pushers to start since they will be disabled in the main config
     config.send_federation = True
 
-    tls_server_context_factory = context_factory.ServerContextFactory(config)
-    tls_client_options_factory = context_factory.ClientTLSOptionsFactory(config)
-
-    ps = FederationSenderServer(
+    ss = FederationSenderServer(
         config.server_name,
         db_config=config.database_config,
-        tls_server_context_factory=tls_server_context_factory,
-        tls_client_options_factory=tls_client_options_factory,
         config=config,
         version_string="Synapse/" + get_version_string(synapse),
         database_engine=database_engine,
     )
 
-    ps.setup()
-    ps.start_listening(config.worker_listeners)
+    ss.setup()
 
     def start():
-        ps.get_datastore().start_profiling()
+        ss.config.read_certificate_from_disk()
+        ss.tls_server_context_factory = context_factory.ServerContextFactory(config)
+        ss.tls_client_options_factory = context_factory.ClientTLSOptionsFactory(
+            config
+        )
+        ss.start_listening(config.worker_listeners)
+        ss.get_datastore().start_profiling()
 
     reactor.callWhenRunning(start)
     _base.start_worker_reactor("synapse-federation-sender", config)
diff --git a/synapse/app/frontend_proxy.py b/synapse/app/frontend_proxy.py
index f5c61dec..d9ef6edc 100644
--- a/synapse/app/frontend_proxy.py
+++ b/synapse/app/frontend_proxy.py
@@ -241,23 +241,23 @@ def start(config_options):
 
     database_engine = create_engine(config.database_config)
 
-    tls_server_context_factory = context_factory.ServerContextFactory(config)
-    tls_client_options_factory = context_factory.ClientTLSOptionsFactory(config)
-
     ss = FrontendProxyServer(
         config.server_name,
         db_config=config.database_config,
-        tls_server_context_factory=tls_server_context_factory,
-        tls_client_options_factory=tls_client_options_factory,
         config=config,
         version_string="Synapse/" + get_version_string(synapse),
         database_engine=database_engine,
     )
 
     ss.setup()
-    ss.start_listening(config.worker_listeners)
 
     def start():
+        ss.config.read_certificate_from_disk()
+        ss.tls_server_context_factory = context_factory.ServerContextFactory(config)
+        ss.tls_client_options_factory = context_factory.ClientTLSOptionsFactory(
+            config
+        )
+        ss.start_listening(config.worker_listeners)
         ss.get_datastore().start_profiling()
 
     reactor.callWhenRunning(start)
diff --git a/synapse/app/homeserver.py b/synapse/app/homeserver.py
index f3ac3d19..250a17ce 100755
--- a/synapse/app/homeserver.py
+++ b/synapse/app/homeserver.py
@@ -13,10 +13,13 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+
 import gc
 import logging
 import os
+import signal
 import sys
+import traceback
 
 from six import iteritems
 
@@ -25,6 +28,7 @@ from prometheus_client import Gauge
 
 from twisted.application import service
 from twisted.internet import defer, reactor
+from twisted.protocols.tls import TLSMemoryBIOFactory
 from twisted.web.resource import EncodingResourceWrapper, NoResource
 from twisted.web.server import GzipEncoderFactory
 from twisted.web.static import File
@@ -82,6 +86,7 @@ def gz_wrap(r):
 
 class SynapseHomeServer(HomeServer):
     DATASTORE_CLASS = DataStore
+    _listening_services = []
 
     def _listener_http(self, config, listener_config):
         port = listener_config["port"]
@@ -90,7 +95,9 @@ class SynapseHomeServer(HomeServer):
         site_tag = listener_config.get("tag", port)
 
         if tls and config.no_tls:
-            return
+            raise ConfigError(
+                "Listener on port %i has TLS enabled, but no_tls is set" % (port,),
+            )
 
         resources = {}
         for res in listener_config["resources"]:
@@ -119,7 +126,7 @@ class SynapseHomeServer(HomeServer):
         root_resource = create_resource_tree(resources, root_resource)
 
         if tls:
-            listen_ssl(
+            return listen_ssl(
                 bind_addresses,
                 port,
                 SynapseSite(
@@ -133,7 +140,7 @@ class SynapseHomeServer(HomeServer):
             )
 
         else:
-            listen_tcp(
+            return listen_tcp(
                 bind_addresses,
                 port,
                 SynapseSite(
@@ -144,7 +151,6 @@ class SynapseHomeServer(HomeServer):
                     self.version_string,
                 )
             )
-        logger.info("Synapse now listening on port %d", port)
 
     def _configure_named_resource(self, name, compress=False):
         """Build a resource map for a named resource
@@ -240,7 +246,9 @@ class SynapseHomeServer(HomeServer):
 
         for listener in config.listeners:
             if listener["type"] == "http":
-                self._listener_http(config, listener)
+                self._listening_services.extend(
+                    self._listener_http(config, listener)
+                )
             elif listener["type"] == "manhole":
                 listen_tcp(
                     listener["bind_addresses"],
@@ -320,12 +328,21 @@ def setup(config_options):
         # generating config files and shouldn't try to continue.
         sys.exit(0)
 
-    synapse.config.logger.setup_logging(config, use_worker_options=False)
+    sighup_callbacks = []
+    synapse.config.logger.setup_logging(
+        config,
+        use_worker_options=False,
+        register_sighup=sighup_callbacks.append
+    )
 
-    events.USE_FROZEN_DICTS = config.use_frozen_dicts
+    def handle_sighup(*args, **kwargs):
+        for i in sighup_callbacks:
+            i(*args, **kwargs)
 
-    tls_server_context_factory = context_factory.ServerContextFactory(config)
-    tls_client_options_factory = context_factory.ClientTLSOptionsFactory(config)
+    if hasattr(signal, "SIGHUP"):
+        signal.signal(signal.SIGHUP, handle_sighup)
+
+    events.USE_FROZEN_DICTS = config.use_frozen_dicts
 
     database_engine = create_engine(config.database_config)
     config.database_config["args"]["cp_openfun"] = database_engine.on_new_connection
@@ -333,8 +350,6 @@ def setup(config_options):
     hs = SynapseHomeServer(
         config.server_name,
         db_config=config.database_config,
-        tls_server_context_factory=tls_server_context_factory,
-        tls_client_options_factory=tls_client_options_factory,
         config=config,
         version_string="Synapse/" + get_version_string(synapse),
         database_engine=database_engine,
@@ -361,12 +376,78 @@ def setup(config_options):
     logger.info("Database prepared in %s.", config.database_config['name'])
 
     hs.setup()
-    hs.start_listening()
 
+    def refresh_certificate(*args):
+        """
+        Refresh the TLS certificates that Synapse is using by re-reading them
+        from disk and updating the TLS context factories to use them.
+        """
+        logging.info("Reloading certificate from disk...")
+        hs.config.read_certificate_from_disk()
+        hs.tls_server_context_factory = context_factory.ServerContextFactory(config)
+        hs.tls_client_options_factory = context_factory.ClientTLSOptionsFactory(
+            config
+        )
+        logging.info("Certificate reloaded.")
+
+        logging.info("Updating context factories...")
+        for i in hs._listening_services:
+            if isinstance(i.factory, TLSMemoryBIOFactory):
+                i.factory = TLSMemoryBIOFactory(
+                    hs.tls_server_context_factory,
+                    False,
+                    i.factory.wrappedFactory
+                )
+        logging.info("Context factories updated.")
+
+    sighup_callbacks.append(refresh_certificate)
+
+    @defer.inlineCallbacks
     def start():
-        hs.get_pusherpool().start()
-        hs.get_datastore().start_profiling()
-        hs.get_datastore().start_doing_background_updates()
+        try:
+            # Check if the certificate is still valid.
+            cert_days_remaining = hs.config.is_disk_cert_valid()
+
+            if hs.config.acme_enabled:
+                # If ACME is enabled, we might need to provision a certificate
+                # before starting.
+                acme = hs.get_acme_handler()
+
+                # Start up the webservices which we will respond to ACME
+                # challenges with.
+                yield acme.start_listening()
+
+                # We want to reprovision if cert_days_remaining is None (meaning no
+                # certificate exists), or the days remaining number it returns
+                # is less than our re-registration threshold.
+                if (cert_days_remaining is None) or (
+                    not cert_days_remaining > hs.config.acme_reprovision_threshold
+                ):
+                    yield acme.provision_certificate()
+
+            # Read the certificate from disk and build the context factories for
+            # TLS.
+            hs.config.read_certificate_from_disk()
+            hs.tls_server_context_factory = context_factory.ServerContextFactory(config)
+            hs.tls_client_options_factory = context_factory.ClientTLSOptionsFactory(
+                config
+            )
+
+            # It is now safe to start your Synapse.
+            hs.start_listening()
+            hs.get_pusherpool().start()
+            hs.get_datastore().start_profiling()
+            hs.get_datastore().start_doing_background_updates()
+        except Exception as e:
+            # If a DeferredList failed (like in listening on the ACME listener),
+            # we need to print the subfailure explicitly.
+            if isinstance(e, defer.FirstError):
+                e.subFailure.printTraceback(sys.stderr)
+                sys.exit(1)
+
+            # Something else went wrong when starting. Print it and bail out.
+            traceback.print_exc(file=sys.stderr)
+            sys.exit(1)
 
     reactor.callWhenRunning(start)
 
diff --git a/synapse/app/media_repository.py b/synapse/app/media_repository.py
index acc0487a..4ecf6403 100644
--- a/synapse/app/media_repository.py
+++ b/synapse/app/media_repository.py
@@ -151,23 +151,23 @@ def start(config_options):
 
     database_engine = create_engine(config.database_config)
 
-    tls_server_context_factory = context_factory.ServerContextFactory(config)
-    tls_client_options_factory = context_factory.ClientTLSOptionsFactory(config)
-
     ss = MediaRepositoryServer(
         config.server_name,
         db_config=config.database_config,
-        tls_server_context_factory=tls_server_context_factory,
-        tls_client_options_factory=tls_client_options_factory,
         config=config,
         version_string="Synapse/" + get_version_string(synapse),
         database_engine=database_engine,
     )
 
     ss.setup()
-    ss.start_listening(config.worker_listeners)
 
     def start():
+        ss.config.read_certificate_from_disk()
+        ss.tls_server_context_factory = context_factory.ServerContextFactory(config)
+        ss.tls_client_options_factory = context_factory.ClientTLSOptionsFactory(
+            config
+        )
+        ss.start_listening(config.worker_listeners)
         ss.get_datastore().start_profiling()
 
     reactor.callWhenRunning(start)
diff --git a/synapse/app/user_dir.py b/synapse/app/user_dir.py
index 0a5f62b5..176d55a7 100644
--- a/synapse/app/user_dir.py
+++ b/synapse/app/user_dir.py
@@ -211,24 +211,24 @@ def start(config_options):
     # Force the pushers to start since they will be disabled in the main config
     config.update_user_directory = True
 
-    tls_server_context_factory = context_factory.ServerContextFactory(config)
-    tls_client_options_factory = context_factory.ClientTLSOptionsFactory(config)
-
-    ps = UserDirectoryServer(
+    ss = UserDirectoryServer(
         config.server_name,
         db_config=config.database_config,
-        tls_server_context_factory=tls_server_context_factory,
-        tls_client_options_factory=tls_client_options_factory,
         config=config,
         version_string="Synapse/" + get_version_string(synapse),
         database_engine=database_engine,
     )
 
-    ps.setup()
-    ps.start_listening(config.worker_listeners)
+    ss.setup()
 
     def start():
-        ps.get_datastore().start_profiling()
+        ss.config.read_certificate_from_disk()
+        ss.tls_server_context_factory = context_factory.ServerContextFactory(config)
+        ss.tls_client_options_factory = context_factory.ClientTLSOptionsFactory(
+            config
+        )
+        ss.start_listening(config.worker_listeners)
+        ss.get_datastore().start_profiling()
 
     reactor.callWhenRunning(start)
 
diff --git a/synapse/config/_base.py b/synapse/config/_base.py
index fd2d6d52..5858fb92 100644
--- a/synapse/config/_base.py
+++ b/synapse/config/_base.py
@@ -367,7 +367,7 @@ class Config(object):
         if not keys_directory:
             keys_directory = os.path.dirname(config_files[-1])
 
-        config_dir_path = os.path.abspath(keys_directory)
+        self.config_dir_path = os.path.abspath(keys_directory)
 
         specified_config = {}
         for config_file in config_files:
@@ -379,7 +379,7 @@ class Config(object):
 
         server_name = specified_config["server_name"]
         config_string = self.generate_config(
-            config_dir_path=config_dir_path,
+            config_dir_path=self.config_dir_path,
             data_dir_path=os.getcwd(),
             server_name=server_name,
             generate_secrets=False,
diff --git a/synapse/config/consent_config.py b/synapse/config/consent_config.py
index f193a090..9f2e8534 100644
--- a/synapse/config/consent_config.py
+++ b/synapse/config/consent_config.py
@@ -13,6 +13,10 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from os import path
+
+from synapse.config import ConfigError
+
 from ._base import Config
 
 DEFAULT_CONFIG = """\
@@ -85,7 +89,15 @@ class ConsentConfig(Config):
         if consent_config is None:
             return
         self.user_consent_version = str(consent_config["version"])
-        self.user_consent_template_dir = consent_config["template_dir"]
+        self.user_consent_template_dir = self.abspath(
+            consent_config["template_dir"]
+        )
+        if not path.isdir(self.user_consent_template_dir):
+            raise ConfigError(
+                "Could not find template directory '%s'" % (
+                    self.user_consent_template_dir,
+                ),
+            )
         self.user_consent_server_notice_content = consent_config.get(
             "server_notice_content",
         )
diff --git a/synapse/config/key.py b/synapse/config/key.py
index 3b11f0cf..dce4b19a 100644
--- a/synapse/config/key.py
+++ b/synapse/config/key.py
@@ -83,9 +83,6 @@ class KeyConfig(Config):
         # a secret which is used to sign access tokens. If none is specified,
         # the registration_shared_secret is used, if one is given; otherwise,
         # a secret key is derived from the signing key.
-        #
-        # Note that changing this will invalidate any active access tokens, so
-        # all clients will have to log back in.
         %(macaroon_secret_key)s
 
         # Used to enable access token expiration.
diff --git a/synapse/config/logger.py b/synapse/config/logger.py
index f87efecb..a795e39b 100644
--- a/synapse/config/logger.py
+++ b/synapse/config/logger.py
@@ -127,7 +127,7 @@ class LoggingConfig(Config):
                 )
 
 
-def setup_logging(config, use_worker_options=False):
+def setup_logging(config, use_worker_options=False, register_sighup=None):
     """ Set up python logging
 
     Args:
@@ -136,7 +136,16 @@ def setup_logging(config, use_worker_options=False):
 
         use_worker_options (bool): True to use 'worker_log_config' and
             'worker_log_file' options instead of 'log_config' and 'log_file'.
+
+        register_sighup (func | None): Function to call to register a
+            sighup handler.
     """
+    if not register_sighup:
+        if getattr(signal, "SIGHUP"):
+            register_sighup = lambda x: signal.signal(signal.SIGHUP, x)
+        else:
+            register_sighup = lambda x: None
+
     log_config = (config.worker_log_config if use_worker_options
                   else config.log_config)
     log_file = (config.worker_log_file if use_worker_options
@@ -198,13 +207,7 @@ def setup_logging(config, use_worker_options=False):
 
         load_log_config()
 
-    # TODO(paul): obviously this is a terrible mechanism for
-    #   stealing SIGHUP, because it means no other part of synapse
-    #   can use it instead. If we want to catch SIGHUP anywhere
-    #   else as well, I'd suggest we find a nicer way to broadcast
-    #   it around.
-    if getattr(signal, "SIGHUP"):
-        signal.signal(signal.SIGHUP, sighup)
+    register_sighup(sighup)
 
     # make sure that the first thing we log is a thing we can grep backwards
     # for
diff --git a/synapse/config/registration.py b/synapse/config/registration.py
index 6c2b543b..d808a989 100644
--- a/synapse/config/registration.py
+++ b/synapse/config/registration.py
@@ -50,6 +50,10 @@ class RegistrationConfig(Config):
                 raise ConfigError('Invalid auto_join_rooms entry %s' % (room_alias,))
         self.autocreate_auto_join_rooms = config.get("autocreate_auto_join_rooms", True)
 
+        self.disable_msisdn_registration = (
+            config.get("disable_msisdn_registration", False)
+        )
+
     def default_config(self, generate_secrets=False, **kwargs):
         if generate_secrets:
             registration_shared_secret = 'registration_shared_secret: "%s"' % (
@@ -70,16 +74,21 @@ class RegistrationConfig(Config):
         #     - email
         #     - msisdn
 
+        # Explicitly disable asking for MSISDNs from the registration
+        # flow (overrides registrations_require_3pid if MSISDNs are set as required)
+        #
+        # disable_msisdn_registration = True
+
         # Mandate that users are only allowed to associate certain formats of
         # 3PIDs with accounts on this server.
         #
         # allowed_local_3pids:
         #     - medium: email
-        #       pattern: ".*@matrix\\.org"
+        #       pattern: '.*@matrix\\.org'
         #     - medium: email
-        #       pattern: ".*@vector\\.im"
+        #       pattern: '.*@vector\\.im'
         #     - medium: msisdn
-        #       pattern: "\\+44"
+        #       pattern: '\\+44'
 
         # If set, allows registration by anyone who also has the shared
         # secret, even if registration is otherwise disabled.
diff --git a/synapse/config/server.py b/synapse/config/server.py
index fb577910..268a43ff 100644
--- a/synapse/config/server.py
+++ b/synapse/config/server.py
@@ -256,8 +256,12 @@ class ServerConfig(Config):
         #
         # web_client_location: "/path/to/web/root"
 
-        # The public-facing base URL for the client API (not including _matrix/...)
-        # public_baseurl: https://example.com:8448/
+        # The public-facing base URL that clients use to access this HS
+        # (not including _matrix/...). This is the same URL a user would
+        # enter into the 'custom HS URL' field on their client. If you
+        # use synapse with a reverse proxy, this should be the URL to reach
+        # synapse via the proxy.
+        # public_baseurl: https://example.com/
 
         # Set the soft limit on the number of file descriptors synapse can use
         # Zero is used to indicate synapse should set the soft limit to the
@@ -420,19 +424,18 @@ class ServerConfig(Config):
                                   " service on the given port.")
 
 
-def is_threepid_reserved(config, threepid):
+def is_threepid_reserved(reserved_threepids, threepid):
     """Check the threepid against the reserved threepid config
     Args:
-        config(ServerConfig) - to access server config attributes
+        reserved_threepids([dict]) - list of reserved threepids
         threepid(dict) - The threepid to test for
 
     Returns:
         boolean Is the threepid undertest reserved_user
     """
 
-    for tp in config.mau_limits_reserved_threepids:
-        if (threepid['medium'] == tp['medium']
-                and threepid['address'] == tp['address']):
+    for tp in reserved_threepids:
+        if (threepid['medium'] == tp['medium'] and threepid['address'] == tp['address']):
             return True
     return False
 
diff --git a/synapse/config/tls.py b/synapse/config/tls.py
index fef1ea99..b5f2cfd9 100644
--- a/synapse/config/tls.py
+++ b/synapse/config/tls.py
@@ -13,83 +13,196 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import logging
 import os
-import subprocess
+import warnings
+from datetime import datetime
 from hashlib import sha256
 
 from unpaddedbase64 import encode_base64
 
 from OpenSSL import crypto
 
-from ._base import Config
+from synapse.config._base import Config
 
-GENERATE_DH_PARAMS = False
+logger = logging.getLogger()
 
 
 class TlsConfig(Config):
     def read_config(self, config):
-        self.tls_certificate = self.read_tls_certificate(
-            config.get("tls_certificate_path")
-        )
-        self.tls_certificate_file = config.get("tls_certificate_path")
 
+        acme_config = config.get("acme", None)
+        if acme_config is None:
+            acme_config = {}
+
+        self.acme_enabled = acme_config.get("enabled", False)
+        self.acme_url = acme_config.get(
+            "url", u"https://acme-v01.api.letsencrypt.org/directory"
+        )
+        self.acme_port = acme_config.get("port", 80)
+        self.acme_bind_addresses = acme_config.get("bind_addresses", ['::', '0.0.0.0'])
+        self.acme_reprovision_threshold = acme_config.get("reprovision_threshold", 30)
+
+        self.tls_certificate_file = self.abspath(config.get("tls_certificate_path"))
+        self.tls_private_key_file = self.abspath(config.get("tls_private_key_path"))
+        self._original_tls_fingerprints = config["tls_fingerprints"]
+        self.tls_fingerprints = list(self._original_tls_fingerprints)
         self.no_tls = config.get("no_tls", False)
 
-        if self.no_tls:
-            self.tls_private_key = None
-        else:
-            self.tls_private_key = self.read_tls_private_key(
-                config.get("tls_private_key_path")
-            )
+        # This config option applies to non-federation HTTP clients
+        # (e.g. for talking to recaptcha, identity servers, and such)
+        # It should never be used in production, and is intended for
+        # use only when running tests.
+        self.use_insecure_ssl_client_just_for_testing_do_not_use = config.get(
+            "use_insecure_ssl_client_just_for_testing_do_not_use"
+        )
 
-        self.tls_dh_params_path = self.check_file(
-            config.get("tls_dh_params_path"), "tls_dh_params"
+        self.tls_certificate = None
+        self.tls_private_key = None
+
+    def is_disk_cert_valid(self):
+        """
+        Is the certificate we have on disk valid, and if so, for how long?
+
+        Returns:
+            int: Days remaining of certificate validity.
+            None: No certificate exists.
+        """
+        if not os.path.exists(self.tls_certificate_file):
+            return None
+
+        try:
+            with open(self.tls_certificate_file, 'rb') as f:
+                cert_pem = f.read()
+        except Exception:
+            logger.exception("Failed to read existing certificate off disk!")
+            raise
+
+        try:
+            tls_certificate = crypto.load_certificate(crypto.FILETYPE_PEM, cert_pem)
+        except Exception:
+            logger.exception("Failed to parse existing certificate off disk!")
+            raise
+
+        # YYYYMMDDhhmmssZ -- in UTC
+        expires_on = datetime.strptime(
+            tls_certificate.get_notAfter().decode('ascii'), "%Y%m%d%H%M%SZ"
         )
+        now = datetime.utcnow()
+        days_remaining = (expires_on - now).days
+        return days_remaining
+
+    def read_certificate_from_disk(self):
+        """
+        Read the certificates from disk.
+        """
+        self.tls_certificate = self.read_tls_certificate(self.tls_certificate_file)
+
+        # Check if it is self-signed, and issue a warning if so.
+        if self.tls_certificate.get_issuer() == self.tls_certificate.get_subject():
+            warnings.warn(
+                (
+                    "Self-signed TLS certificates will not be accepted by Synapse 1.0. "
+                    "Please either provide a valid certificate, or use Synapse's ACME "
+                    "support to provision one."
+                )
+            )
+
+        if not self.no_tls:
+            self.tls_private_key = self.read_tls_private_key(self.tls_private_key_file)
 
-        self.tls_fingerprints = config["tls_fingerprints"]
+        self.tls_fingerprints = list(self._original_tls_fingerprints)
 
         # Check that our own certificate is included in the list of fingerprints
         # and include it if it is not.
         x509_certificate_bytes = crypto.dump_certificate(
-            crypto.FILETYPE_ASN1,
-            self.tls_certificate
+            crypto.FILETYPE_ASN1, self.tls_certificate
         )
         sha256_fingerprint = encode_base64(sha256(x509_certificate_bytes).digest())
         sha256_fingerprints = set(f["sha256"] for f in self.tls_fingerprints)
         if sha256_fingerprint not in sha256_fingerprints:
             self.tls_fingerprints.append({u"sha256": sha256_fingerprint})
 
-        # This config option applies to non-federation HTTP clients
-        # (e.g. for talking to recaptcha, identity servers, and such)
-        # It should never be used in production, and is intended for
-        # use only when running tests.
-        self.use_insecure_ssl_client_just_for_testing_do_not_use = config.get(
-            "use_insecure_ssl_client_just_for_testing_do_not_use"
-        )
-
     def default_config(self, config_dir_path, server_name, **kwargs):
         base_key_name = os.path.join(config_dir_path, server_name)
 
         tls_certificate_path = base_key_name + ".tls.crt"
         tls_private_key_path = base_key_name + ".tls.key"
-        tls_dh_params_path = base_key_name + ".tls.dh"
-
-        return """\
-        # PEM encoded X509 certificate for TLS.
-        # You can replace the self-signed certificate that synapse
-        # autogenerates on launch with your own SSL certificate + key pair
-        # if you like.  Any required intermediary certificates can be
-        # appended after the primary certificate in hierarchical order.
+
+        # this is to avoid the max line length. Sorrynotsorry
+        proxypassline = (
+            'ProxyPass /.well-known/acme-challenge '
+            'http://localhost:8009/.well-known/acme-challenge'
+        )
+
+        return (
+            """\
+        # PEM-encoded X509 certificate for TLS.
+        # This certificate, as of Synapse 1.0, will need to be a valid and verifiable
+        # certificate, signed by a recognised Certificate Authority.
+        #
+        # See 'ACME support' below to enable auto-provisioning this certificate via
+        # Let's Encrypt.
+        #
         tls_certificate_path: "%(tls_certificate_path)s"
 
-        # PEM encoded private key for TLS
+        # PEM-encoded private key for TLS
         tls_private_key_path: "%(tls_private_key_path)s"
 
-        # PEM dh parameters for ephemeral keys
-        tls_dh_params_path: "%(tls_dh_params_path)s"
-
-        # Don't bind to the https port
-        no_tls: False
+        # ACME support: This will configure Synapse to request a valid TLS certificate
+        # for your configured `server_name` via Let's Encrypt.
+        #
+        # Note that provisioning a certificate in this way requires port 80 to be
+        # routed to Synapse so that it can complete the http-01 ACME challenge.
+        # By default, if you enable ACME support, Synapse will attempt to listen on
+        # port 80 for incoming http-01 challenges - however, this will likely fail
+        # with 'Permission denied' or a similar error.
+        #
+        # There are a couple of potential solutions to this:
+        #
+        #  * If you already have an Apache, Nginx, or similar listening on port 80,
+        #    you can configure Synapse to use an alternate port, and have your web
+        #    server forward the requests. For example, assuming you set 'port: 8009'
+        #    below, on Apache, you would write:
+        #
+        #    %(proxypassline)s
+        #
+        #  * Alternatively, you can use something like `authbind` to give Synapse
+        #    permission to listen on port 80.
+        #
+        acme:
+            # ACME support is disabled by default. Uncomment the following line
+            # to enable it.
+            #
+            # enabled: true
+
+            # Endpoint to use to request certificates. If you only want to test,
+            # use Let's Encrypt's staging url:
+            #     https://acme-staging.api.letsencrypt.org/directory
+            #
+            # url: https://acme-v01.api.letsencrypt.org/directory
+
+            # Port number to listen on for the HTTP-01 challenge. Change this if
+            # you are forwarding connections through Apache/Nginx/etc.
+            #
+            # port: 80
+
+            # Local addresses to listen on for incoming connections.
+            # Again, you may want to change this if you are forwarding connections
+            # through Apache/Nginx/etc.
+            #
+            # bind_addresses: ['::', '0.0.0.0']
+
+            # How many days remaining on a certificate before it is renewed.
+            #
+            # reprovision_threshold: 30
+
+        # If your server runs behind a reverse-proxy which terminates TLS connections
+        # (for both client and federation connections), it may be useful to disable
+        # All TLS support for incoming connections. Setting no_tls to True will
+        # do so (and avoid the need to give synapse a TLS private key).
+        #
+        # no_tls: True
 
         # List of allowed TLS fingerprints for this server to publish along
         # with the signing keys for this server. Other matrix servers that
@@ -118,7 +231,10 @@ class TlsConfig(Config):
         #
         tls_fingerprints: []
         # tls_fingerprints: [{"sha256": "<base64_encoded_sha256_fingerprint>"}]
-        """ % locals()
+
+        """
+            % locals()
+        )
 
     def read_tls_certificate(self, cert_path):
         cert_pem = self.read_file(cert_path, "tls_certificate")
@@ -127,69 +243,3 @@ class TlsConfig(Config):
     def read_tls_private_key(self, private_key_path):
         private_key_pem = self.read_file(private_key_path, "tls_private_key")
         return crypto.load_privatekey(crypto.FILETYPE_PEM, private_key_pem)
-
-    def generate_files(self, config):
-        tls_certificate_path = config["tls_certificate_path"]
-        tls_private_key_path = config["tls_private_key_path"]
-        tls_dh_params_path = config["tls_dh_params_path"]
-
-        if not self.path_exists(tls_private_key_path):
-            with open(tls_private_key_path, "wb") as private_key_file:
-                tls_private_key = crypto.PKey()
-                tls_private_key.generate_key(crypto.TYPE_RSA, 2048)
-                private_key_pem = crypto.dump_privatekey(
-                    crypto.FILETYPE_PEM, tls_private_key
-                )
-                private_key_file.write(private_key_pem)
-        else:
-            with open(tls_private_key_path) as private_key_file:
-                private_key_pem = private_key_file.read()
-                tls_private_key = crypto.load_privatekey(
-                    crypto.FILETYPE_PEM, private_key_pem
-                )
-
-        if not self.path_exists(tls_certificate_path):
-            with open(tls_certificate_path, "wb") as certificate_file:
-                cert = crypto.X509()
-                subject = cert.get_subject()
-                subject.CN = config["server_name"]
-
-                cert.set_serial_number(1000)
-                cert.gmtime_adj_notBefore(0)
-                cert.gmtime_adj_notAfter(10 * 365 * 24 * 60 * 60)
-                cert.set_issuer(cert.get_subject())
-                cert.set_pubkey(tls_private_key)
-
-                cert.sign(tls_private_key, 'sha256')
-
-                cert_pem = crypto.dump_certificate(crypto.FILETYPE_PEM, cert)
-
-                certificate_file.write(cert_pem)
-
-        if not self.path_exists(tls_dh_params_path):
-            if GENERATE_DH_PARAMS:
-                subprocess.check_call([
-                    "openssl", "dhparam",
-                    "-outform", "PEM",
-                    "-out", tls_dh_params_path,
-                    "2048"
-                ])
-            else:
-                with open(tls_dh_params_path, "w") as dh_params_file:
-                    dh_params_file.write(
-                        "2048-bit DH parameters taken from rfc3526\n"
-                        "-----BEGIN DH PARAMETERS-----\n"
-                        "MIIBCAKCAQEA///////////JD9qiIWjC"
-                        "NMTGYouA3BzRKQJOCIpnzHQCC76mOxOb\n"
-                        "IlFKCHmONATd75UZs806QxswKwpt8l8U"
-                        "N0/hNW1tUcJF5IW1dmJefsb0TELppjft\n"
-                        "awv/XLb0Brft7jhr+1qJn6WunyQRfEsf"
-                        "5kkoZlHs5Fs9wgB8uKFjvwWY2kg2HFXT\n"
-                        "mmkWP6j9JM9fg2VdI9yjrZYcYvNWIIVS"
-                        "u57VKQdwlpZtZww1Tkq8mATxdGwIyhgh\n"
-                        "fDKQXkYuNs474553LBgOhgObJ4Oi7Aei"
-                        "j7XFXfBvTFLJ3ivL9pVYFxg5lUl86pVq\n"
-                        "5RXSJhiY+gUQFXKOWoqsqmj/////////"
-                        "/wIBAg==\n"
-                        "-----END DH PARAMETERS-----\n"
-                    )
diff --git a/synapse/crypto/context_factory.py b/synapse/crypto/context_factory.py
index 02b76dfc..286ad801 100644
--- a/synapse/crypto/context_factory.py
+++ b/synapse/crypto/context_factory.py
@@ -17,6 +17,7 @@ from zope.interface import implementer
 
 from OpenSSL import SSL, crypto
 from twisted.internet._sslverify import _defaultCurveName
+from twisted.internet.abstract import isIPAddress, isIPv6Address
 from twisted.internet.interfaces import IOpenSSLClientConnectionCreator
 from twisted.internet.ssl import CertificateOptions, ContextFactory
 from twisted.python.failure import Failure
@@ -46,8 +47,10 @@ class ServerContextFactory(ContextFactory):
         if not config.no_tls:
             context.use_privatekey(config.tls_private_key)
 
-        context.load_tmp_dh(config.tls_dh_params_path)
-        context.set_cipher_list("!ADH:HIGH+kEDH:!AECDH:HIGH+kEECDH")
+        # https://hynek.me/articles/hardening-your-web-servers-ssl-ciphers/
+        context.set_cipher_list(
+            "ECDH+AESGCM:ECDH+CHACHA20:ECDH+AES256:ECDH+AES128:!aNULL:!SHA1"
+        )
 
     def getContext(self):
         return self._context
@@ -96,8 +99,14 @@ class ClientTLSOptions(object):
 
     def __init__(self, hostname, ctx):
         self._ctx = ctx
-        self._hostname = hostname
-        self._hostnameBytes = _idnaBytes(hostname)
+
+        if isIPAddress(hostname) or isIPv6Address(hostname):
+            self._hostnameBytes = hostname.encode('ascii')
+            self._sendSNI = False
+        else:
+            self._hostnameBytes = _idnaBytes(hostname)
+            self._sendSNI = True
+
         ctx.set_info_callback(
             _tolerateErrors(self._identityVerifyingInfoCallback)
         )
@@ -109,7 +118,9 @@ class ClientTLSOptions(object):
         return connection
 
     def _identityVerifyingInfoCallback(self, connection, where, ret):
-        if where & SSL.SSL_CB_HANDSHAKE_START:
+        # Literal IPv4 and IPv6 addresses are not permitted
+        # as host names according to the RFCs
+        if where & SSL.SSL_CB_HANDSHAKE_START and self._sendSNI:
             connection.set_tlsext_host_name(self._hostnameBytes)
 
 
diff --git a/synapse/crypto/event_signing.py b/synapse/crypto/event_signing.py
index 8774b289..1dfa727f 100644
--- a/synapse/crypto/event_signing.py
+++ b/synapse/crypto/event_signing.py
@@ -23,14 +23,14 @@ from signedjson.sign import sign_json
 from unpaddedbase64 import decode_base64, encode_base64
 
 from synapse.api.errors import Codes, SynapseError
-from synapse.events.utils import prune_event
+from synapse.events.utils import prune_event, prune_event_dict
 
 logger = logging.getLogger(__name__)
 
 
 def check_event_content_hash(event, hash_algorithm=hashlib.sha256):
     """Check whether the hash for this PDU matches the contents"""
-    name, expected_hash = compute_content_hash(event, hash_algorithm)
+    name, expected_hash = compute_content_hash(event.get_pdu_json(), hash_algorithm)
     logger.debug("Expecting hash: %s", encode_base64(expected_hash))
 
     # some malformed events lack a 'hashes'. Protect against it being missing
@@ -59,35 +59,70 @@ def check_event_content_hash(event, hash_algorithm=hashlib.sha256):
     return message_hash_bytes == expected_hash
 
 
-def compute_content_hash(event, hash_algorithm):
-    event_json = event.get_pdu_json()
-    event_json.pop("age_ts", None)
-    event_json.pop("unsigned", None)
-    event_json.pop("signatures", None)
-    event_json.pop("hashes", None)
-    event_json.pop("outlier", None)
-    event_json.pop("destinations", None)
+def compute_content_hash(event_dict, hash_algorithm):
+    """Compute the content hash of an event, which is the hash of the
+    unredacted event.
 
-    event_json_bytes = encode_canonical_json(event_json)
+    Args:
+        event_dict (dict): The unredacted event as a dict
+        hash_algorithm: A hasher from `hashlib`, e.g. hashlib.sha256, to use
+            to hash the event
+
+    Returns:
+        tuple[str, bytes]: A tuple of the name of hash and the hash as raw
+        bytes.
+    """
+    event_dict = dict(event_dict)
+    event_dict.pop("age_ts", None)
+    event_dict.pop("unsigned", None)
+    event_dict.pop("signatures", None)
+    event_dict.pop("hashes", None)
+    event_dict.pop("outlier", None)
+    event_dict.pop("destinations", None)
+
+    event_json_bytes = encode_canonical_json(event_dict)
 
     hashed = hash_algorithm(event_json_bytes)
     return (hashed.name, hashed.digest())
 
 
 def compute_event_reference_hash(event, hash_algorithm=hashlib.sha256):
+    """Computes the event reference hash. This is the hash of the redacted
+    event.
+
+    Args:
+        event (FrozenEvent)
+        hash_algorithm: A hasher from `hashlib`, e.g. hashlib.sha256, to use
+            to hash the event
+
+    Returns:
+        tuple[str, bytes]: A tuple of the name of hash and the hash as raw
+        bytes.
+    """
     tmp_event = prune_event(event)
-    event_json = tmp_event.get_pdu_json()
-    event_json.pop("signatures", None)
-    event_json.pop("age_ts", None)
-    event_json.pop("unsigned", None)
-    event_json_bytes = encode_canonical_json(event_json)
+    event_dict = tmp_event.get_pdu_json()
+    event_dict.pop("signatures", None)
+    event_dict.pop("age_ts", None)
+    event_dict.pop("unsigned", None)
+    event_json_bytes = encode_canonical_json(event_dict)
     hashed = hash_algorithm(event_json_bytes)
     return (hashed.name, hashed.digest())
 
 
-def compute_event_signature(event, signature_name, signing_key):
-    tmp_event = prune_event(event)
-    redact_json = tmp_event.get_pdu_json()
+def compute_event_signature(event_dict, signature_name, signing_key):
+    """Compute the signature of the event for the given name and key.
+
+    Args:
+        event_dict (dict): The event as a dict
+        signature_name (str): The name of the entity signing the event
+            (typically the server's hostname).
+        signing_key (syutil.crypto.SigningKey): The key to sign with
+
+    Returns:
+        dict[str, dict[str, str]]: Returns a dictionary in the same format of
+        an event's signatures field.
+    """
+    redact_json = prune_event_dict(event_dict)
     redact_json.pop("age_ts", None)
     redact_json.pop("unsigned", None)
     logger.debug("Signing event: %s", encode_canonical_json(redact_json))
@@ -96,25 +131,25 @@ def compute_event_signature(event, signature_name, signing_key):
     return redact_json["signatures"]
 
 
-def add_hashes_and_signatures(event, signature_name, signing_key,
+def add_hashes_and_signatures(event_dict, signature_name, signing_key,
                               hash_algorithm=hashlib.sha256):
-    # if hasattr(event, "old_state_events"):
-    #     state_json_bytes = encode_canonical_json(
-    #         [e.event_id for e in event.old_state_events.values()]
-    #     )
-    #     hashed = hash_algorithm(state_json_bytes)
-    #     event.state_hash = {
-    #         hashed.name: encode_base64(hashed.digest())
-    #     }
-
-    name, digest = compute_content_hash(event, hash_algorithm=hash_algorithm)
-
-    if not hasattr(event, "hashes"):
-        event.hashes = {}
-    event.hashes[name] = encode_base64(digest)
-
-    event.signatures = compute_event_signature(
-        event,
+    """Add content hash and sign the event
+
+    Args:
+        event_dict (dict): The event to add hashes to and sign
+        signature_name (str): The name of the entity signing the event
+            (typically the server's hostname).
+        signing_key (syutil.crypto.SigningKey): The key to sign with
+        hash_algorithm: A hasher from `hashlib`, e.g. hashlib.sha256, to use
+            to hash the event
+    """
+
+    name, digest = compute_content_hash(event_dict, hash_algorithm=hash_algorithm)
+
+    event_dict.setdefault("hashes", {})[name] = encode_base64(digest)
+
+    event_dict["signatures"] = compute_event_signature(
+        event_dict,
         signature_name=signature_name,
         signing_key=signing_key,
     )
diff --git a/synapse/crypto/keyclient.py b/synapse/crypto/keyclient.py
deleted file mode 100644
index d40e4b85..00000000
--- a/synapse/crypto/keyclient.py
+++ /dev/null
@@ -1,149 +0,0 @@
-# -*- coding: utf-8 -*-
-# Copyright 2014-2016 OpenMarket Ltd
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-import logging
-
-from six.moves import urllib
-
-from canonicaljson import json
-
-from twisted.internet import defer, reactor
-from twisted.internet.error import ConnectError
-from twisted.internet.protocol import Factory
-from twisted.names.error import DomainError
-from twisted.web.http import HTTPClient
-
-from synapse.http.endpoint import matrix_federation_endpoint
-from synapse.util import logcontext
-
-logger = logging.getLogger(__name__)
-
-KEY_API_V2 = "/_matrix/key/v2/server/%s"
-
-
-@defer.inlineCallbacks
-def fetch_server_key(server_name, tls_client_options_factory, key_id):
-    """Fetch the keys for a remote server."""
-
-    factory = SynapseKeyClientFactory()
-    factory.path = KEY_API_V2 % (urllib.parse.quote(key_id), )
-    factory.host = server_name
-    endpoint = matrix_federation_endpoint(
-        reactor, server_name, tls_client_options_factory, timeout=30
-    )
-
-    for i in range(5):
-        try:
-            with logcontext.PreserveLoggingContext():
-                protocol = yield endpoint.connect(factory)
-                server_response, server_certificate = yield protocol.remote_key
-                defer.returnValue((server_response, server_certificate))
-        except SynapseKeyClientError as e:
-            logger.warn("Error getting key for %r: %s", server_name, e)
-            if e.status.startswith(b"4"):
-                # Don't retry for 4xx responses.
-                raise IOError("Cannot get key for %r" % server_name)
-        except (ConnectError, DomainError) as e:
-            logger.warn("Error getting key for %r: %s", server_name, e)
-        except Exception:
-            logger.exception("Error getting key for %r", server_name)
-    raise IOError("Cannot get key for %r" % server_name)
-
-
-class SynapseKeyClientError(Exception):
-    """The key wasn't retrieved from the remote server."""
-    status = None
-    pass
-
-
-class SynapseKeyClientProtocol(HTTPClient):
-    """Low level HTTPS client which retrieves an application/json response from
-    the server and extracts the X.509 certificate for the remote peer from the
-    SSL connection."""
-
-    timeout = 30
-
-    def __init__(self):
-        self.remote_key = defer.Deferred()
-        self.host = None
-        self._peer = None
-
-    def connectionMade(self):
-        self._peer = self.transport.getPeer()
-        logger.debug("Connected to %s", self._peer)
-
-        if not isinstance(self.path, bytes):
-            self.path = self.path.encode('ascii')
-
-        if not isinstance(self.host, bytes):
-            self.host = self.host.encode('ascii')
-
-        self.sendCommand(b"GET", self.path)
-        if self.host:
-            self.sendHeader(b"Host", self.host)
-        self.endHeaders()
-        self.timer = reactor.callLater(
-            self.timeout,
-            self.on_timeout
-        )
-
-    def errback(self, error):
-        if not self.remote_key.called:
-            self.remote_key.errback(error)
-
-    def callback(self, result):
-        if not self.remote_key.called:
-            self.remote_key.callback(result)
-
-    def handleStatus(self, version, status, message):
-        if status != b"200":
-            # logger.info("Non-200 response from %s: %s %s",
-            #            self.transport.getHost(), status, message)
-            error = SynapseKeyClientError(
-                "Non-200 response %r from %r" % (status, self.host)
-            )
-            error.status = status
-            self.errback(error)
-            self.transport.abortConnection()
-
-    def handleResponse(self, response_body_bytes):
-        try:
-            json_response = json.loads(response_body_bytes)
-        except ValueError:
-            # logger.info("Invalid JSON response from %s",
-            #            self.transport.getHost())
-            self.transport.abortConnection()
-            return
-
-        certificate = self.transport.getPeerCertificate()
-        self.callback((json_response, certificate))
-        self.transport.abortConnection()
-        self.timer.cancel()
-
-    def on_timeout(self):
-        logger.debug(
-            "Timeout waiting for response from %s: %s",
-            self.host, self._peer,
-        )
-        self.errback(IOError("Timeout waiting for response"))
-        self.transport.abortConnection()
-
-
-class SynapseKeyClientFactory(Factory):
-    def protocol(self):
-        protocol = SynapseKeyClientProtocol()
-        protocol.path = self.path
-        protocol.host = self.host
-        return protocol
diff --git a/synapse/crypto/keyring.py b/synapse/crypto/keyring.py
index 515ebbc1..3a96980b 100644
--- a/synapse/crypto/keyring.py
+++ b/synapse/crypto/keyring.py
@@ -14,10 +14,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import hashlib
 import logging
 from collections import namedtuple
 
+from six.moves import urllib
+
 from signedjson.key import (
     decode_verify_key_bytes,
     encode_verify_key_base64,
@@ -30,13 +31,11 @@ from signedjson.sign import (
     signature_ids,
     verify_signed_json,
 )
-from unpaddedbase64 import decode_base64, encode_base64
+from unpaddedbase64 import decode_base64
 
-from OpenSSL import crypto
 from twisted.internet import defer
 
 from synapse.api.errors import Codes, SynapseError
-from synapse.crypto.keyclient import fetch_server_key
 from synapse.util import logcontext, unwrapFirstError
 from synapse.util.logcontext import (
     LoggingContext,
@@ -503,31 +502,16 @@ class Keyring(object):
             if requested_key_id in keys:
                 continue
 
-            (response, tls_certificate) = yield fetch_server_key(
-                server_name, self.hs.tls_client_options_factory, requested_key_id
+            response = yield self.client.get_json(
+                destination=server_name,
+                path="/_matrix/key/v2/server/" + urllib.parse.quote(requested_key_id),
+                ignore_backoff=True,
             )
 
             if (u"signatures" not in response
                     or server_name not in response[u"signatures"]):
                 raise KeyLookupError("Key response not signed by remote server")
 
-            if "tls_fingerprints" not in response:
-                raise KeyLookupError("Key response missing TLS fingerprints")
-
-            certificate_bytes = crypto.dump_certificate(
-                crypto.FILETYPE_ASN1, tls_certificate
-            )
-            sha256_fingerprint = hashlib.sha256(certificate_bytes).digest()
-            sha256_fingerprint_b64 = encode_base64(sha256_fingerprint)
-
-            response_sha256_fingerprints = set()
-            for fingerprint in response[u"tls_fingerprints"]:
-                if u"sha256" in fingerprint:
-                    response_sha256_fingerprints.add(fingerprint[u"sha256"])
-
-            if sha256_fingerprint_b64 not in response_sha256_fingerprints:
-                raise KeyLookupError("TLS certificate not allowed by fingerprints")
-
             response_keys = yield self.process_v2_response(
                 from_server=server_name,
                 requested_ids=[requested_key_id],
diff --git a/synapse/event_auth.py b/synapse/event_auth.py
index c81d8e67..8f9e330d 100644
--- a/synapse/event_auth.py
+++ b/synapse/event_auth.py
@@ -20,17 +20,25 @@ from signedjson.key import decode_verify_key_bytes
 from signedjson.sign import SignatureVerifyException, verify_signed_json
 from unpaddedbase64 import decode_base64
 
-from synapse.api.constants import KNOWN_ROOM_VERSIONS, EventTypes, JoinRules, Membership
+from synapse.api.constants import (
+    KNOWN_ROOM_VERSIONS,
+    EventFormatVersions,
+    EventTypes,
+    JoinRules,
+    Membership,
+    RoomVersions,
+)
 from synapse.api.errors import AuthError, EventSizeError, SynapseError
 from synapse.types import UserID, get_domain_from_id
 
 logger = logging.getLogger(__name__)
 
 
-def check(event, auth_events, do_sig_check=True, do_size_check=True):
+def check(room_version, event, auth_events, do_sig_check=True, do_size_check=True):
     """ Checks if this event is correctly authed.
 
     Args:
+        room_version (str): the version of the room
         event: the event being checked.
         auth_events (dict: event-key -> event): the existing room state.
 
@@ -48,7 +56,6 @@ def check(event, auth_events, do_sig_check=True, do_size_check=True):
 
     if do_sig_check:
         sender_domain = get_domain_from_id(event.sender)
-        event_id_domain = get_domain_from_id(event.event_id)
 
         is_invite_via_3pid = (
             event.type == EventTypes.Member
@@ -65,9 +72,13 @@ def check(event, auth_events, do_sig_check=True, do_size_check=True):
             if not is_invite_via_3pid:
                 raise AuthError(403, "Event not signed by sender's server")
 
-        # Check the event_id's domain has signed the event
-        if not event.signatures.get(event_id_domain):
-            raise AuthError(403, "Event not signed by sending server")
+        if event.format_version in (EventFormatVersions.V1,):
+            # Only older room versions have event IDs to check.
+            event_id_domain = get_domain_from_id(event.event_id)
+
+            # Check the origin domain has signed the event
+            if not event.signatures.get(event_id_domain):
+                raise AuthError(403, "Event not signed by sending server")
 
     if auth_events is None:
         # Oh, we don't know what the state of the room was, so we
@@ -167,7 +178,7 @@ def check(event, auth_events, do_sig_check=True, do_size_check=True):
         _check_power_levels(event, auth_events)
 
     if event.type == EventTypes.Redaction:
-        check_redaction(event, auth_events)
+        check_redaction(room_version, event, auth_events)
 
     logger.debug("Allowing! %s", event)
 
@@ -421,7 +432,7 @@ def _can_send_event(event, auth_events):
     return True
 
 
-def check_redaction(event, auth_events):
+def check_redaction(room_version, event, auth_events):
     """Check whether the event sender is allowed to redact the target event.
 
     Returns:
@@ -441,10 +452,16 @@ def check_redaction(event, auth_events):
     if user_level >= redact_level:
         return False
 
-    redacter_domain = get_domain_from_id(event.event_id)
-    redactee_domain = get_domain_from_id(event.redacts)
-    if redacter_domain == redactee_domain:
+    if room_version in (RoomVersions.V1, RoomVersions.V2,):
+        redacter_domain = get_domain_from_id(event.event_id)
+        redactee_domain = get_domain_from_id(event.redacts)
+        if redacter_domain == redactee_domain:
+            return True
+    elif room_version == RoomVersions.V3:
+        event.internal_metadata.recheck_redaction = True
         return True
+    else:
+        raise RuntimeError("Unrecognized room version %r" % (room_version,))
 
     raise AuthError(
         403,
diff --git a/synapse/events/__init__.py b/synapse/events/__init__.py
index 84c75495..20c1ab42 100644
--- a/synapse/events/__init__.py
+++ b/synapse/events/__init__.py
@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 # Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2019 New Vector Ltd
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -18,6 +19,9 @@ from distutils.util import strtobool
 
 import six
 
+from unpaddedbase64 import encode_base64
+
+from synapse.api.constants import KNOWN_ROOM_VERSIONS, EventFormatVersions, RoomVersions
 from synapse.util.caches import intern_dict
 from synapse.util.frozenutils import freeze
 
@@ -41,8 +45,13 @@ class _EventInternalMetadata(object):
     def is_outlier(self):
         return getattr(self, "outlier", False)
 
-    def is_invite_from_remote(self):
-        return getattr(self, "invite_from_remote", False)
+    def is_out_of_band_membership(self):
+        """Whether this is an out of band membership, like an invite or an invite
+        rejection. This is needed as those events are marked as outliers, but
+        they still need to be processed as if they're new events (e.g. updating
+        invite state in the database, relaying to clients, etc).
+        """
+        return getattr(self, "out_of_band_membership", False)
 
     def get_send_on_behalf_of(self):
         """Whether this server should send the event on behalf of another server.
@@ -53,6 +62,21 @@ class _EventInternalMetadata(object):
         """
         return getattr(self, "send_on_behalf_of", None)
 
+    def need_to_check_redaction(self):
+        """Whether the redaction event needs to be rechecked when fetching
+        from the database.
+
+        Starting in room v3 redaction events are accepted up front, and later
+        checked to see if the redacter and redactee's domains match.
+
+        If the sender of the redaction event is allowed to redact any event
+        due to auth rules, then this will always return false.
+
+        Returns:
+            bool
+        """
+        return getattr(self, "recheck_redaction", False)
+
 
 def _event_dict_property(key):
     # We want to be able to use hasattr with the event dict properties.
@@ -179,6 +203,8 @@ class EventBase(object):
 
 
 class FrozenEvent(EventBase):
+    format_version = EventFormatVersions.V1  # All events of this type are V1
+
     def __init__(self, event_dict, internal_metadata_dict={}, rejected_reason=None):
         event_dict = dict(event_dict)
 
@@ -213,22 +239,136 @@ class FrozenEvent(EventBase):
             rejected_reason=rejected_reason,
         )
 
-    @staticmethod
-    def from_event(event):
-        e = FrozenEvent(
-            event.get_pdu_json()
+    def __str__(self):
+        return self.__repr__()
+
+    def __repr__(self):
+        return "<FrozenEvent event_id='%s', type='%s', state_key='%s'>" % (
+            self.get("event_id", None),
+            self.get("type", None),
+            self.get("state_key", None),
+        )
+
+
+class FrozenEventV2(EventBase):
+    format_version = EventFormatVersions.V2  # All events of this type are V2
+
+    def __init__(self, event_dict, internal_metadata_dict={}, rejected_reason=None):
+        event_dict = dict(event_dict)
+
+        # Signatures is a dict of dicts, and this is faster than doing a
+        # copy.deepcopy
+        signatures = {
+            name: {sig_id: sig for sig_id, sig in sigs.items()}
+            for name, sigs in event_dict.pop("signatures", {}).items()
+        }
+
+        assert "event_id" not in event_dict
+
+        unsigned = dict(event_dict.pop("unsigned", {}))
+
+        # We intern these strings because they turn up a lot (especially when
+        # caching).
+        event_dict = intern_dict(event_dict)
+
+        if USE_FROZEN_DICTS:
+            frozen_dict = freeze(event_dict)
+        else:
+            frozen_dict = event_dict
+
+        self._event_id = None
+        self.type = event_dict["type"]
+        if "state_key" in event_dict:
+            self.state_key = event_dict["state_key"]
+
+        super(FrozenEventV2, self).__init__(
+            frozen_dict,
+            signatures=signatures,
+            unsigned=unsigned,
+            internal_metadata_dict=internal_metadata_dict,
+            rejected_reason=rejected_reason,
         )
 
-        e.internal_metadata = event.internal_metadata
+    @property
+    def event_id(self):
+        # We have to import this here as otherwise we get an import loop which
+        # is hard to break.
+        from synapse.crypto.event_signing import compute_event_reference_hash
 
-        return e
+        if self._event_id:
+            return self._event_id
+        self._event_id = "$" + encode_base64(compute_event_reference_hash(self)[1])
+        return self._event_id
+
+    def prev_event_ids(self):
+        """Returns the list of prev event IDs. The order matches the order
+        specified in the event, though there is no meaning to it.
+
+        Returns:
+            list[str]: The list of event IDs of this event's prev_events
+        """
+        return self.prev_events
+
+    def auth_event_ids(self):
+        """Returns the list of auth event IDs. The order matches the order
+        specified in the event, though there is no meaning to it.
+
+        Returns:
+            list[str]: The list of event IDs of this event's auth_events
+        """
+        return self.auth_events
 
     def __str__(self):
         return self.__repr__()
 
     def __repr__(self):
-        return "<FrozenEvent event_id='%s', type='%s', state_key='%s'>" % (
-            self.get("event_id", None),
+        return "<FrozenEventV2 event_id='%s', type='%s', state_key='%s'>" % (
+            self.event_id,
             self.get("type", None),
             self.get("state_key", None),
         )
+
+
+def room_version_to_event_format(room_version):
+    """Converts a room version string to the event format
+
+    Args:
+        room_version (str)
+
+    Returns:
+        int
+    """
+    if room_version not in KNOWN_ROOM_VERSIONS:
+        # We should have already checked version, so this should not happen
+        raise RuntimeError("Unrecognized room version %s" % (room_version,))
+
+    if room_version in (
+        RoomVersions.V1, RoomVersions.V2, RoomVersions.STATE_V2_TEST,
+    ):
+        return EventFormatVersions.V1
+    elif room_version in (RoomVersions.V3,):
+        return EventFormatVersions.V2
+    else:
+        raise RuntimeError("Unrecognized room version %s" % (room_version,))
+
+
+def event_type_from_format_version(format_version):
+    """Returns the python type to use to construct an Event object for the
+    given event format version.
+
+    Args:
+        format_version (int): The event format version
+
+    Returns:
+        type: A type that can be initialized as per the initializer of
+        `FrozenEvent`
+    """
+
+    if format_version == EventFormatVersions.V1:
+        return FrozenEvent
+    elif format_version == EventFormatVersions.V2:
+        return FrozenEventV2
+    else:
+        raise Exception(
+            "No event format %r" % (format_version,)
+        )
diff --git a/synapse/events/builder.py b/synapse/events/builder.py
index e662eaef..06e01be9 100644
--- a/synapse/events/builder.py
+++ b/synapse/events/builder.py
@@ -13,63 +13,270 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import copy
+import attr
 
+from twisted.internet import defer
+
+from synapse.api.constants import (
+    KNOWN_EVENT_FORMAT_VERSIONS,
+    KNOWN_ROOM_VERSIONS,
+    MAX_DEPTH,
+    EventFormatVersions,
+)
+from synapse.crypto.event_signing import add_hashes_and_signatures
 from synapse.types import EventID
 from synapse.util.stringutils import random_string
 
-from . import EventBase, FrozenEvent, _event_dict_property
+from . import (
+    _EventInternalMetadata,
+    event_type_from_format_version,
+    room_version_to_event_format,
+)
+
+
+@attr.s(slots=True, cmp=False, frozen=True)
+class EventBuilder(object):
+    """A format independent event builder used to build up the event content
+    before signing the event.
+
+    (Note that while objects of this class are frozen, the
+    content/unsigned/internal_metadata fields are still mutable)
+
+    Attributes:
+        format_version (int): Event format version
+        room_id (str)
+        type (str)
+        sender (str)
+        content (dict)
+        unsigned (dict)
+        internal_metadata (_EventInternalMetadata)
+
+        _state (StateHandler)
+        _auth (synapse.api.Auth)
+        _store (DataStore)
+        _clock (Clock)
+        _hostname (str): The hostname of the server creating the event
+        _signing_key: The signing key to use to sign the event as the server
+    """
+
+    _state = attr.ib()
+    _auth = attr.ib()
+    _store = attr.ib()
+    _clock = attr.ib()
+    _hostname = attr.ib()
+    _signing_key = attr.ib()
+
+    format_version = attr.ib()
+
+    room_id = attr.ib()
+    type = attr.ib()
+    sender = attr.ib()
+
+    content = attr.ib(default=attr.Factory(dict))
+    unsigned = attr.ib(default=attr.Factory(dict))
+
+    # These only exist on a subset of events, so they raise AttributeError if
+    # someone tries to get them when they don't exist.
+    _state_key = attr.ib(default=None)
+    _redacts = attr.ib(default=None)
 
+    internal_metadata = attr.ib(default=attr.Factory(lambda: _EventInternalMetadata({})))
 
-class EventBuilder(EventBase):
-    def __init__(self, key_values={}, internal_metadata_dict={}):
-        signatures = copy.deepcopy(key_values.pop("signatures", {}))
-        unsigned = copy.deepcopy(key_values.pop("unsigned", {}))
+    @property
+    def state_key(self):
+        if self._state_key is not None:
+            return self._state_key
 
-        super(EventBuilder, self).__init__(
-            key_values,
-            signatures=signatures,
-            unsigned=unsigned,
-            internal_metadata_dict=internal_metadata_dict,
+        raise AttributeError("state_key")
+
+    def is_state(self):
+        return self._state_key is not None
+
+    @defer.inlineCallbacks
+    def build(self, prev_event_ids):
+        """Transform into a fully signed and hashed event
+
+        Args:
+            prev_event_ids (list[str]): The event IDs to use as the prev events
+
+        Returns:
+            Deferred[FrozenEvent]
+        """
+
+        state_ids = yield self._state.get_current_state_ids(
+            self.room_id, prev_event_ids,
+        )
+        auth_ids = yield self._auth.compute_auth_events(
+            self, state_ids,
         )
 
-    event_id = _event_dict_property("event_id")
-    state_key = _event_dict_property("state_key")
-    type = _event_dict_property("type")
+        if self.format_version == EventFormatVersions.V1:
+            auth_events = yield self._store.add_event_hashes(auth_ids)
+            prev_events = yield self._store.add_event_hashes(prev_event_ids)
+        else:
+            auth_events = auth_ids
+            prev_events = prev_event_ids
+
+        old_depth = yield self._store.get_max_depth_of(
+            prev_event_ids,
+        )
+        depth = old_depth + 1
+
+        # we cap depth of generated events, to ensure that they are not
+        # rejected by other servers (and so that they can be persisted in
+        # the db)
+        depth = min(depth, MAX_DEPTH)
+
+        event_dict = {
+            "auth_events": auth_events,
+            "prev_events": prev_events,
+            "type": self.type,
+            "room_id": self.room_id,
+            "sender": self.sender,
+            "content": self.content,
+            "unsigned": self.unsigned,
+            "depth": depth,
+            "prev_state": [],
+        }
+
+        if self.is_state():
+            event_dict["state_key"] = self._state_key
 
-    def build(self):
-        return FrozenEvent.from_event(self)
+        if self._redacts is not None:
+            event_dict["redacts"] = self._redacts
+
+        defer.returnValue(
+            create_local_event_from_event_dict(
+                clock=self._clock,
+                hostname=self._hostname,
+                signing_key=self._signing_key,
+                format_version=self.format_version,
+                event_dict=event_dict,
+                internal_metadata_dict=self.internal_metadata.get_dict(),
+            )
+        )
 
 
 class EventBuilderFactory(object):
-    def __init__(self, clock, hostname):
-        self.clock = clock
-        self.hostname = hostname
+    def __init__(self, hs):
+        self.clock = hs.get_clock()
+        self.hostname = hs.hostname
+        self.signing_key = hs.config.signing_key[0]
+
+        self.store = hs.get_datastore()
+        self.state = hs.get_state_handler()
+        self.auth = hs.get_auth()
+
+    def new(self, room_version, key_values):
+        """Generate an event builder appropriate for the given room version
+
+        Args:
+            room_version (str): Version of the room that we're creating an
+                event builder for
+            key_values (dict): Fields used as the basis of the new event
+
+        Returns:
+            EventBuilder
+        """
+
+        # There's currently only the one event version defined
+        if room_version not in KNOWN_ROOM_VERSIONS:
+            raise Exception(
+                "No event format defined for version %r" % (room_version,)
+            )
+
+        return EventBuilder(
+            store=self.store,
+            state=self.state,
+            auth=self.auth,
+            clock=self.clock,
+            hostname=self.hostname,
+            signing_key=self.signing_key,
+            format_version=room_version_to_event_format(room_version),
+            type=key_values["type"],
+            state_key=key_values.get("state_key"),
+            room_id=key_values["room_id"],
+            sender=key_values["sender"],
+            content=key_values.get("content", {}),
+            unsigned=key_values.get("unsigned", {}),
+            redacts=key_values.get("redacts", None),
+        )
+
+
+def create_local_event_from_event_dict(clock, hostname, signing_key,
+                                       format_version, event_dict,
+                                       internal_metadata_dict=None):
+    """Takes a fully formed event dict, ensuring that fields like `origin`
+    and `origin_server_ts` have correct values for a locally produced event,
+    then signs and hashes it.
+
+    Args:
+        clock (Clock)
+        hostname (str)
+        signing_key
+        format_version (int)
+        event_dict (dict)
+        internal_metadata_dict (dict|None)
+
+    Returns:
+        FrozenEvent
+    """
+
+    # There's currently only the one event version defined
+    if format_version not in KNOWN_EVENT_FORMAT_VERSIONS:
+        raise Exception(
+            "No event format defined for version %r" % (format_version,)
+        )
+
+    if internal_metadata_dict is None:
+        internal_metadata_dict = {}
+
+    time_now = int(clock.time_msec())
+
+    if format_version == EventFormatVersions.V1:
+        event_dict["event_id"] = _create_event_id(clock, hostname)
+
+    event_dict["origin"] = hostname
+    event_dict["origin_server_ts"] = time_now
+
+    event_dict.setdefault("unsigned", {})
+    age = event_dict["unsigned"].pop("age", 0)
+    event_dict["unsigned"].setdefault("age_ts", time_now - age)
+
+    event_dict.setdefault("signatures", {})
+
+    add_hashes_and_signatures(
+        event_dict,
+        hostname,
+        signing_key,
+    )
+    return event_type_from_format_version(format_version)(
+        event_dict, internal_metadata_dict=internal_metadata_dict,
+    )
 
-        self.event_id_count = 0
 
-    def create_event_id(self):
-        i = str(self.event_id_count)
-        self.event_id_count += 1
+# A counter used when generating new event IDs
+_event_id_counter = 0
 
-        local_part = str(int(self.clock.time())) + i + random_string(5)
 
-        e_id = EventID(local_part, self.hostname)
+def _create_event_id(clock, hostname):
+    """Create a new event ID
 
-        return e_id.to_string()
+    Args:
+        clock (Clock)
+        hostname (str): The server name for the event ID
 
-    def new(self, key_values={}):
-        key_values["event_id"] = self.create_event_id()
+    Returns:
+        str
+    """
 
-        time_now = int(self.clock.time_msec())
+    global _event_id_counter
 
-        key_values.setdefault("origin", self.hostname)
-        key_values.setdefault("origin_server_ts", time_now)
+    i = str(_event_id_counter)
+    _event_id_counter += 1
 
-        key_values.setdefault("unsigned", {})
-        age = key_values["unsigned"].pop("age", 0)
-        key_values["unsigned"].setdefault("age_ts", time_now - age)
+    local_part = str(int(clock.time())) + i + random_string(5)
 
-        key_values["signatures"] = {}
+    e_id = EventID(local_part, hostname)
 
-        return EventBuilder(key_values=key_values,)
+    return e_id.to_string()
diff --git a/synapse/events/utils.py b/synapse/events/utils.py
index 652941ca..07fccdd8 100644
--- a/synapse/events/utils.py
+++ b/synapse/events/utils.py
@@ -38,8 +38,31 @@ def prune_event(event):
     This is used when we "redact" an event. We want to remove all fields that
     the user has specified, but we do want to keep necessary information like
     type, state_key etc.
+
+    Args:
+        event (FrozenEvent)
+
+    Returns:
+        FrozenEvent
+    """
+    pruned_event_dict = prune_event_dict(event.get_dict())
+
+    from . import event_type_from_format_version
+    return event_type_from_format_version(event.format_version)(
+        pruned_event_dict, event.internal_metadata.get_dict()
+    )
+
+
+def prune_event_dict(event_dict):
+    """Redacts the event_dict in the same way as `prune_event`, except it
+    operates on dicts rather than event objects
+
+    Args:
+        event_dict (dict)
+
+    Returns:
+        dict: A copy of the pruned event dict
     """
-    event_type = event.type
 
     allowed_keys = [
         "event_id",
@@ -59,13 +82,13 @@ def prune_event(event):
         "membership",
     ]
 
-    event_dict = event.get_dict()
+    event_type = event_dict["type"]
 
     new_content = {}
 
     def add_fields(*fields):
         for field in fields:
-            if field in event.content:
+            if field in event_dict["content"]:
                 new_content[field] = event_dict["content"][field]
 
     if event_type == EventTypes.Member:
@@ -98,17 +121,17 @@ def prune_event(event):
 
     allowed_fields["content"] = new_content
 
-    allowed_fields["unsigned"] = {}
+    unsigned = {}
+    allowed_fields["unsigned"] = unsigned
 
-    if "age_ts" in event.unsigned:
-        allowed_fields["unsigned"]["age_ts"] = event.unsigned["age_ts"]
-    if "replaces_state" in event.unsigned:
-        allowed_fields["unsigned"]["replaces_state"] = event.unsigned["replaces_state"]
+    event_unsigned = event_dict.get("unsigned", {})
 
-    return type(event)(
-        allowed_fields,
-        internal_metadata_dict=event.internal_metadata.get_dict()
-    )
+    if "age_ts" in event_unsigned:
+        unsigned["age_ts"] = event_unsigned["age_ts"]
+    if "replaces_state" in event_unsigned:
+        unsigned["replaces_state"] = event_unsigned["replaces_state"]
+
+    return allowed_fields
 
 
 def _copy_field(src, dst, field):
@@ -244,6 +267,7 @@ def serialize_event(e, time_now_ms, as_client_event=True,
     Returns:
         dict
     """
+
     # FIXME(erikj): To handle the case of presence events and the like
     if not isinstance(e, EventBase):
         return e
@@ -253,6 +277,8 @@ def serialize_event(e, time_now_ms, as_client_event=True,
     # Should this strip out None's?
     d = {k: v for k, v in e.get_dict().items()}
 
+    d["event_id"] = e.event_id
+
     if "age_ts" in d["unsigned"]:
         d["unsigned"]["age"] = time_now_ms - d["unsigned"]["age_ts"]
         del d["unsigned"]["age_ts"]
diff --git a/synapse/events/validator.py b/synapse/events/validator.py
index cf184748..a072674b 100644
--- a/synapse/events/validator.py
+++ b/synapse/events/validator.py
@@ -15,23 +15,29 @@
 
 from six import string_types
 
-from synapse.api.constants import EventTypes, Membership
+from synapse.api.constants import EventFormatVersions, EventTypes, Membership
 from synapse.api.errors import SynapseError
 from synapse.types import EventID, RoomID, UserID
 
 
 class EventValidator(object):
+    def validate_new(self, event):
+        """Validates the event has roughly the right format
 
-    def validate(self, event):
-        EventID.from_string(event.event_id)
-        RoomID.from_string(event.room_id)
+        Args:
+            event (FrozenEvent)
+        """
+        self.validate_builder(event)
+
+        if event.format_version == EventFormatVersions.V1:
+            EventID.from_string(event.event_id)
 
         required = [
-            # "auth_events",
+            "auth_events",
             "content",
-            # "hashes",
+            "hashes",
             "origin",
-            # "prev_events",
+            "prev_events",
             "sender",
             "type",
         ]
@@ -41,8 +47,25 @@ class EventValidator(object):
                 raise SynapseError(400, "Event does not have key %s" % (k,))
 
         # Check that the following keys have string values
-        strings = [
+        event_strings = [
             "origin",
+        ]
+
+        for s in event_strings:
+            if not isinstance(getattr(event, s), string_types):
+                raise SynapseError(400, "'%s' not a string type" % (s,))
+
+    def validate_builder(self, event):
+        """Validates that the builder/event has roughly the right format. Only
+        checks values that we expect a proto event to have, rather than all the
+        fields an event would have
+
+        Args:
+            event (EventBuilder|FrozenEvent)
+        """
+
+        strings = [
+            "room_id",
             "sender",
             "type",
         ]
@@ -54,22 +77,7 @@ class EventValidator(object):
             if not isinstance(getattr(event, s), string_types):
                 raise SynapseError(400, "Not '%s' a string type" % (s,))
 
-        if event.type == EventTypes.Member:
-            if "membership" not in event.content:
-                raise SynapseError(400, "Content has not membership key")
-
-            if event.content["membership"] not in Membership.LIST:
-                raise SynapseError(400, "Invalid membership key")
-
-        # Check that the following keys have dictionary values
-        # TODO
-
-        # Check that the following keys have the correct format for DAGs
-        # TODO
-
-    def validate_new(self, event):
-        self.validate(event)
-
+        RoomID.from_string(event.room_id)
         UserID.from_string(event.sender)
 
         if event.type == EventTypes.Message:
@@ -86,9 +94,16 @@ class EventValidator(object):
         elif event.type == EventTypes.Name:
             self._ensure_strings(event.content, ["name"])
 
+        elif event.type == EventTypes.Member:
+            if "membership" not in event.content:
+                raise SynapseError(400, "Content has not membership key")
+
+            if event.content["membership"] not in Membership.LIST:
+                raise SynapseError(400, "Invalid membership key")
+
     def _ensure_strings(self, d, keys):
         for s in keys:
             if s not in d:
                 raise SynapseError(400, "'%s' not in content" % (s,))
             if not isinstance(d[s], string_types):
-                raise SynapseError(400, "Not '%s' a string type" % (s,))
+                raise SynapseError(400, "'%s' not a string type" % (s,))
diff --git a/synapse/federation/federation_base.py b/synapse/federation/federation_base.py
index b7ad729c..a7a2ec45 100644
--- a/synapse/federation/federation_base.py
+++ b/synapse/federation/federation_base.py
@@ -20,10 +20,10 @@ import six
 from twisted.internet import defer
 from twisted.internet.defer import DeferredList
 
-from synapse.api.constants import MAX_DEPTH, EventTypes, Membership
+from synapse.api.constants import MAX_DEPTH, EventTypes, Membership, RoomVersions
 from synapse.api.errors import Codes, SynapseError
 from synapse.crypto.event_signing import check_event_content_hash
-from synapse.events import FrozenEvent
+from synapse.events import event_type_from_format_version
 from synapse.events.utils import prune_event
 from synapse.http.servlet import assert_params_in_dict
 from synapse.types import get_domain_from_id
@@ -43,8 +43,8 @@ class FederationBase(object):
         self._clock = hs.get_clock()
 
     @defer.inlineCallbacks
-    def _check_sigs_and_hash_and_fetch(self, origin, pdus, outlier=False,
-                                       include_none=False):
+    def _check_sigs_and_hash_and_fetch(self, origin, pdus, room_version,
+                                       outlier=False, include_none=False):
         """Takes a list of PDUs and checks the signatures and hashs of each
         one. If a PDU fails its signature check then we check if we have it in
         the database and if not then request if from the originating server of
@@ -56,13 +56,17 @@ class FederationBase(object):
         a new list.
 
         Args:
+            origin (str)
             pdu (list)
-            outlier (bool)
+            room_version (str)
+            outlier (bool): Whether the events are outliers or not
+            include_none (str): Whether to include None in the returned list
+                for events that have failed their checks
 
         Returns:
             Deferred : A list of PDUs that have valid signatures and hashes.
         """
-        deferreds = self._check_sigs_and_hashes(pdus)
+        deferreds = self._check_sigs_and_hashes(room_version, pdus)
 
         @defer.inlineCallbacks
         def handle_check_result(pdu, deferred):
@@ -84,6 +88,7 @@ class FederationBase(object):
                     res = yield self.get_pdu(
                         destinations=[pdu.origin],
                         event_id=pdu.event_id,
+                        room_version=room_version,
                         outlier=outlier,
                         timeout=10000,
                     )
@@ -116,16 +121,17 @@ class FederationBase(object):
         else:
             defer.returnValue([p for p in valid_pdus if p])
 
-    def _check_sigs_and_hash(self, pdu):
+    def _check_sigs_and_hash(self, room_version, pdu):
         return logcontext.make_deferred_yieldable(
-            self._check_sigs_and_hashes([pdu])[0],
+            self._check_sigs_and_hashes(room_version, [pdu])[0],
         )
 
-    def _check_sigs_and_hashes(self, pdus):
+    def _check_sigs_and_hashes(self, room_version, pdus):
         """Checks that each of the received events is correctly signed by the
         sending server.
 
         Args:
+            room_version (str): The room version of the PDUs
             pdus (list[FrozenEvent]): the events to be checked
 
         Returns:
@@ -136,7 +142,7 @@ class FederationBase(object):
               * throws a SynapseError if the signature check failed.
             The deferreds run their callbacks in the sentinel logcontext.
         """
-        deferreds = _check_sigs_on_pdus(self.keyring, pdus)
+        deferreds = _check_sigs_on_pdus(self.keyring, room_version, pdus)
 
         ctx = logcontext.LoggingContext.current_context()
 
@@ -198,16 +204,17 @@ class FederationBase(object):
 
 
 class PduToCheckSig(namedtuple("PduToCheckSig", [
-    "pdu", "redacted_pdu_json", "event_id_domain", "sender_domain", "deferreds",
+    "pdu", "redacted_pdu_json", "sender_domain", "deferreds",
 ])):
     pass
 
 
-def _check_sigs_on_pdus(keyring, pdus):
+def _check_sigs_on_pdus(keyring, room_version, pdus):
     """Check that the given events are correctly signed
 
     Args:
         keyring (synapse.crypto.Keyring): keyring object to do the checks
+        room_version (str): the room version of the PDUs
         pdus (Collection[EventBase]): the events to be checked
 
     Returns:
@@ -220,9 +227,7 @@ def _check_sigs_on_pdus(keyring, pdus):
 
     # we want to check that the event is signed by:
     #
-    # (a) the server which created the event_id
-    #
-    # (b) the sender's server.
+    # (a) the sender's server
     #
     #     - except in the case of invites created from a 3pid invite, which are exempt
     #     from this check, because the sender has to match that of the original 3pid
@@ -236,34 +241,26 @@ def _check_sigs_on_pdus(keyring, pdus):
     #     and signatures are *supposed* to be valid whether or not an event has been
     #     redacted. But this isn't the worst of the ways that 3pid invites are broken.
     #
+    # (b) for V1 and V2 rooms, the server which created the event_id
+    #
     # let's start by getting the domain for each pdu, and flattening the event back
     # to JSON.
+
     pdus_to_check = [
         PduToCheckSig(
             pdu=p,
             redacted_pdu_json=prune_event(p).get_pdu_json(),
-            event_id_domain=get_domain_from_id(p.event_id),
             sender_domain=get_domain_from_id(p.sender),
             deferreds=[],
         )
         for p in pdus
     ]
 
-    # first make sure that the event is signed by the event_id's domain
-    deferreds = keyring.verify_json_objects_for_server([
-        (p.event_id_domain, p.redacted_pdu_json)
-        for p in pdus_to_check
-    ])
-
-    for p, d in zip(pdus_to_check, deferreds):
-        p.deferreds.append(d)
-
-    # now let's look for events where the sender's domain is different to the
-    # event id's domain (normally only the case for joins/leaves), and add additional
-    # checks.
+    # First we check that the sender event is signed by the sender's domain
+    # (except if its a 3pid invite, in which case it may be sent by any server)
     pdus_to_check_sender = [
         p for p in pdus_to_check
-        if p.sender_domain != p.event_id_domain and not _is_invite_via_3pid(p.pdu)
+        if not _is_invite_via_3pid(p.pdu)
     ]
 
     more_deferreds = keyring.verify_json_objects_for_server([
@@ -274,19 +271,43 @@ def _check_sigs_on_pdus(keyring, pdus):
     for p, d in zip(pdus_to_check_sender, more_deferreds):
         p.deferreds.append(d)
 
+    # now let's look for events where the sender's domain is different to the
+    # event id's domain (normally only the case for joins/leaves), and add additional
+    # checks. Only do this if the room version has a concept of event ID domain
+    if room_version in (
+        RoomVersions.V1, RoomVersions.V2, RoomVersions.STATE_V2_TEST,
+    ):
+        pdus_to_check_event_id = [
+            p for p in pdus_to_check
+            if p.sender_domain != get_domain_from_id(p.pdu.event_id)
+        ]
+
+        more_deferreds = keyring.verify_json_objects_for_server([
+            (get_domain_from_id(p.pdu.event_id), p.redacted_pdu_json)
+            for p in pdus_to_check_event_id
+        ])
+
+        for p, d in zip(pdus_to_check_event_id, more_deferreds):
+            p.deferreds.append(d)
+    elif room_version in (RoomVersions.V3,):
+        pass  # No further checks needed, as event IDs are hashes here
+    else:
+        raise RuntimeError("Unrecognized room version %s" % (room_version,))
+
     # replace lists of deferreds with single Deferreds
     return [_flatten_deferred_list(p.deferreds) for p in pdus_to_check]
 
 
 def _flatten_deferred_list(deferreds):
-    """Given a list of one or more deferreds, either return the single deferred, or
-    combine into a DeferredList.
+    """Given a list of deferreds, either return the single deferred,
+    combine into a DeferredList, or return an already resolved deferred.
     """
     if len(deferreds) > 1:
         return DeferredList(deferreds, fireOnOneErrback=True, consumeErrors=True)
-    else:
-        assert len(deferreds) == 1
+    elif len(deferreds) == 1:
         return deferreds[0]
+    else:
+        return defer.succeed(None)
 
 
 def _is_invite_via_3pid(event):
@@ -297,11 +318,12 @@ def _is_invite_via_3pid(event):
     )
 
 
-def event_from_pdu_json(pdu_json, outlier=False):
+def event_from_pdu_json(pdu_json, event_format_version, outlier=False):
     """Construct a FrozenEvent from an event json received over federation
 
     Args:
         pdu_json (object): pdu as received over federation
+        event_format_version (int): The event format version
         outlier (bool): True to mark this event as an outlier
 
     Returns:
@@ -313,7 +335,7 @@ def event_from_pdu_json(pdu_json, outlier=False):
     """
     # we could probably enforce a bunch of other fields here (room_id, sender,
     # origin, etc etc)
-    assert_params_in_dict(pdu_json, ('event_id', 'type', 'depth'))
+    assert_params_in_dict(pdu_json, ('type', 'depth'))
 
     depth = pdu_json['depth']
     if not isinstance(depth, six.integer_types):
@@ -325,8 +347,8 @@ def event_from_pdu_json(pdu_json, outlier=False):
     elif depth > MAX_DEPTH:
         raise SynapseError(400, "Depth too large", Codes.BAD_JSON)
 
-    event = FrozenEvent(
-        pdu_json
+    event = event_type_from_format_version(event_format_version)(
+        pdu_json,
     )
 
     event.internal_metadata.outlier = outlier
diff --git a/synapse/federation/federation_client.py b/synapse/federation/federation_client.py
index d05ed91d..4e4f58b4 100644
--- a/synapse/federation/federation_client.py
+++ b/synapse/federation/federation_client.py
@@ -25,14 +25,19 @@ from prometheus_client import Counter
 
 from twisted.internet import defer
 
-from synapse.api.constants import KNOWN_ROOM_VERSIONS, EventTypes, Membership
+from synapse.api.constants import (
+    KNOWN_ROOM_VERSIONS,
+    EventTypes,
+    Membership,
+    RoomVersions,
+)
 from synapse.api.errors import (
     CodeMessageException,
     FederationDeniedError,
     HttpResponseException,
     SynapseError,
 )
-from synapse.events import builder
+from synapse.events import builder, room_version_to_event_format
 from synapse.federation.federation_base import FederationBase, event_from_pdu_json
 from synapse.util import logcontext, unwrapFirstError
 from synapse.util.caches.expiringcache import ExpiringCache
@@ -66,6 +71,9 @@ class FederationClient(FederationBase):
         self.state = hs.get_state_handler()
         self.transport_layer = hs.get_federation_transport_client()
 
+        self.hostname = hs.hostname
+        self.signing_key = hs.config.signing_key[0]
+
         self._get_pdu_cache = ExpiringCache(
             cache_name="get_pdu_cache",
             clock=self._clock,
@@ -162,13 +170,13 @@ class FederationClient(FederationBase):
 
     @defer.inlineCallbacks
     @log_function
-    def backfill(self, dest, context, limit, extremities):
+    def backfill(self, dest, room_id, limit, extremities):
         """Requests some more historic PDUs for the given context from the
         given destination server.
 
         Args:
             dest (str): The remote home server to ask.
-            context (str): The context to backfill.
+            room_id (str): The room_id to backfill.
             limit (int): The maximum number of PDUs to return.
             extremities (list): List of PDU id and origins of the first pdus
                 we have seen from the context
@@ -183,18 +191,21 @@ class FederationClient(FederationBase):
             return
 
         transaction_data = yield self.transport_layer.backfill(
-            dest, context, extremities, limit)
+            dest, room_id, extremities, limit)
 
         logger.debug("backfill transaction_data=%s", repr(transaction_data))
 
+        room_version = yield self.store.get_room_version(room_id)
+        format_ver = room_version_to_event_format(room_version)
+
         pdus = [
-            event_from_pdu_json(p, outlier=False)
+            event_from_pdu_json(p, format_ver, outlier=False)
             for p in transaction_data["pdus"]
         ]
 
         # FIXME: We should handle signature failures more gracefully.
         pdus[:] = yield logcontext.make_deferred_yieldable(defer.gatherResults(
-            self._check_sigs_and_hashes(pdus),
+            self._check_sigs_and_hashes(room_version, pdus),
             consumeErrors=True,
         ).addErrback(unwrapFirstError))
 
@@ -202,7 +213,8 @@ class FederationClient(FederationBase):
 
     @defer.inlineCallbacks
     @log_function
-    def get_pdu(self, destinations, event_id, outlier=False, timeout=None):
+    def get_pdu(self, destinations, event_id, room_version, outlier=False,
+                timeout=None):
         """Requests the PDU with given origin and ID from the remote home
         servers.
 
@@ -212,6 +224,7 @@ class FederationClient(FederationBase):
         Args:
             destinations (list): Which home servers to query
             event_id (str): event to fetch
+            room_version (str): version of the room
             outlier (bool): Indicates whether the PDU is an `outlier`, i.e. if
                 it's from an arbitary point in the context as opposed to part
                 of the current block of PDUs. Defaults to `False`
@@ -230,6 +243,8 @@ class FederationClient(FederationBase):
 
         pdu_attempts = self.pdu_destination_tried.setdefault(event_id, {})
 
+        format_ver = room_version_to_event_format(room_version)
+
         signed_pdu = None
         for destination in destinations:
             now = self._clock.time_msec()
@@ -245,7 +260,7 @@ class FederationClient(FederationBase):
                 logger.debug("transaction_data %r", transaction_data)
 
                 pdu_list = [
-                    event_from_pdu_json(p, outlier=outlier)
+                    event_from_pdu_json(p, format_ver, outlier=outlier)
                     for p in transaction_data["pdus"]
                 ]
 
@@ -253,7 +268,7 @@ class FederationClient(FederationBase):
                     pdu = pdu_list[0]
 
                     # Check signatures are correct.
-                    signed_pdu = yield self._check_sigs_and_hash(pdu)
+                    signed_pdu = yield self._check_sigs_and_hash(room_version, pdu)
 
                     break
 
@@ -339,12 +354,16 @@ class FederationClient(FederationBase):
             destination, room_id, event_id=event_id,
         )
 
+        room_version = yield self.store.get_room_version(room_id)
+        format_ver = room_version_to_event_format(room_version)
+
         pdus = [
-            event_from_pdu_json(p, outlier=True) for p in result["pdus"]
+            event_from_pdu_json(p, format_ver, outlier=True)
+            for p in result["pdus"]
         ]
 
         auth_chain = [
-            event_from_pdu_json(p, outlier=True)
+            event_from_pdu_json(p, format_ver, outlier=True)
             for p in result.get("auth_chain", [])
         ]
 
@@ -355,7 +374,8 @@ class FederationClient(FederationBase):
         signed_pdus = yield self._check_sigs_and_hash_and_fetch(
             destination,
             [p for p in pdus if p.event_id not in seen_events],
-            outlier=True
+            outlier=True,
+            room_version=room_version,
         )
         signed_pdus.extend(
             seen_events[p.event_id] for p in pdus if p.event_id in seen_events
@@ -364,7 +384,8 @@ class FederationClient(FederationBase):
         signed_auth = yield self._check_sigs_and_hash_and_fetch(
             destination,
             [p for p in auth_chain if p.event_id not in seen_events],
-            outlier=True
+            outlier=True,
+            room_version=room_version,
         )
         signed_auth.extend(
             seen_events[p.event_id] for p in auth_chain if p.event_id in seen_events
@@ -411,6 +432,8 @@ class FederationClient(FederationBase):
             random.shuffle(srvs)
             return srvs
 
+        room_version = yield self.store.get_room_version(room_id)
+
         batch_size = 20
         missing_events = list(missing_events)
         for i in range(0, len(missing_events), batch_size):
@@ -421,6 +444,7 @@ class FederationClient(FederationBase):
                     self.get_pdu,
                     destinations=random_server_list(),
                     event_id=e_id,
+                    room_version=room_version,
                 )
                 for e_id in batch
             ]
@@ -445,13 +469,17 @@ class FederationClient(FederationBase):
             destination, room_id, event_id,
         )
 
+        room_version = yield self.store.get_room_version(room_id)
+        format_ver = room_version_to_event_format(room_version)
+
         auth_chain = [
-            event_from_pdu_json(p, outlier=True)
+            event_from_pdu_json(p, format_ver, outlier=True)
             for p in res["auth_chain"]
         ]
 
         signed_auth = yield self._check_sigs_and_hash_and_fetch(
-            destination, auth_chain, outlier=True
+            destination, auth_chain,
+            outlier=True, room_version=room_version,
         )
 
         signed_auth.sort(key=lambda e: e.depth)
@@ -522,6 +550,8 @@ class FederationClient(FederationBase):
         Does so by asking one of the already participating servers to create an
         event with proper context.
 
+        Returns a fully signed and hashed event.
+
         Note that this does not append any events to any graphs.
 
         Args:
@@ -536,8 +566,10 @@ class FederationClient(FederationBase):
             params (dict[str, str|Iterable[str]]): Query parameters to include in the
                 request.
         Return:
-            Deferred: resolves to a tuple of (origin (str), event (object))
-            where origin is the remote homeserver which generated the event.
+            Deferred[tuple[str, FrozenEvent, int]]: resolves to a tuple of
+            `(origin, event, event_format)` where origin is the remote
+            homeserver which generated the event, and event_format is one of
+            `synapse.api.constants.EventFormatVersions`.
 
             Fails with a ``SynapseError`` if the chosen remote server
             returns a 300/400 code.
@@ -557,6 +589,11 @@ class FederationClient(FederationBase):
                 destination, room_id, user_id, membership, params,
             )
 
+            # Note: If not supplied, the room version may be either v1 or v2,
+            # however either way the event format version will be v1.
+            room_version = ret.get("room_version", RoomVersions.V1)
+            event_format = room_version_to_event_format(room_version)
+
             pdu_dict = ret.get("event", None)
             if not isinstance(pdu_dict, dict):
                 raise InvalidResponseError("Bad 'event' field in response")
@@ -571,17 +608,20 @@ class FederationClient(FederationBase):
             if "prev_state" not in pdu_dict:
                 pdu_dict["prev_state"] = []
 
-            ev = builder.EventBuilder(pdu_dict)
+            ev = builder.create_local_event_from_event_dict(
+                self._clock, self.hostname, self.signing_key,
+                format_version=event_format, event_dict=pdu_dict,
+            )
 
             defer.returnValue(
-                (destination, ev)
+                (destination, ev, event_format)
             )
 
         return self._try_destination_list(
             "make_" + membership, destinations, send_request,
         )
 
-    def send_join(self, destinations, pdu):
+    def send_join(self, destinations, pdu, event_format_version):
         """Sends a join event to one of a list of homeservers.
 
         Doing so will cause the remote server to add the event to the graph,
@@ -591,6 +631,7 @@ class FederationClient(FederationBase):
             destinations (str): Candidate homeservers which are probably
                 participating in the room.
             pdu (BaseEvent): event to be sent
+            event_format_version (int): The event format version
 
         Return:
             Deferred: resolves to a dict with members ``origin`` (a string
@@ -636,12 +677,12 @@ class FederationClient(FederationBase):
             logger.debug("Got content: %s", content)
 
             state = [
-                event_from_pdu_json(p, outlier=True)
+                event_from_pdu_json(p, event_format_version, outlier=True)
                 for p in content.get("state", [])
             ]
 
             auth_chain = [
-                event_from_pdu_json(p, outlier=True)
+                event_from_pdu_json(p, event_format_version, outlier=True)
                 for p in content.get("auth_chain", [])
             ]
 
@@ -650,9 +691,21 @@ class FederationClient(FederationBase):
                 for p in itertools.chain(state, auth_chain)
             }
 
+            room_version = None
+            for e in state:
+                if (e.type, e.state_key) == (EventTypes.Create, ""):
+                    room_version = e.content.get("room_version", RoomVersions.V1)
+                    break
+
+            if room_version is None:
+                # If the state doesn't have a create event then the room is
+                # invalid, and it would fail auth checks anyway.
+                raise SynapseError(400, "No create event in state")
+
             valid_pdus = yield self._check_sigs_and_hash_and_fetch(
                 destination, list(pdus.values()),
                 outlier=True,
+                room_version=room_version,
             )
 
             valid_pdus_map = {
@@ -690,32 +743,75 @@ class FederationClient(FederationBase):
 
     @defer.inlineCallbacks
     def send_invite(self, destination, room_id, event_id, pdu):
-        time_now = self._clock.time_msec()
-        try:
-            code, content = yield self.transport_layer.send_invite(
-                destination=destination,
-                room_id=room_id,
-                event_id=event_id,
-                content=pdu.get_pdu_json(time_now),
-            )
-        except HttpResponseException as e:
-            if e.code == 403:
-                raise e.to_synapse_error()
-            raise
+        room_version = yield self.store.get_room_version(room_id)
+
+        content = yield self._do_send_invite(destination, pdu, room_version)
 
         pdu_dict = content["event"]
 
         logger.debug("Got response to send_invite: %s", pdu_dict)
 
-        pdu = event_from_pdu_json(pdu_dict)
+        room_version = yield self.store.get_room_version(room_id)
+        format_ver = room_version_to_event_format(room_version)
+
+        pdu = event_from_pdu_json(pdu_dict, format_ver)
 
         # Check signatures are correct.
-        pdu = yield self._check_sigs_and_hash(pdu)
+        pdu = yield self._check_sigs_and_hash(room_version, pdu)
 
         # FIXME: We should handle signature failures more gracefully.
 
         defer.returnValue(pdu)
 
+    @defer.inlineCallbacks
+    def _do_send_invite(self, destination, pdu, room_version):
+        """Actually sends the invite, first trying v2 API and falling back to
+        v1 API if necessary.
+
+        Args:
+            destination (str): Target server
+            pdu (FrozenEvent)
+            room_version (str)
+
+        Returns:
+            dict: The event as a dict as returned by the remote server
+        """
+        time_now = self._clock.time_msec()
+
+        try:
+            content = yield self.transport_layer.send_invite_v2(
+                destination=destination,
+                room_id=pdu.room_id,
+                event_id=pdu.event_id,
+                content={
+                    "event": pdu.get_pdu_json(time_now),
+                    "room_version": room_version,
+                    "invite_room_state": pdu.unsigned.get("invite_room_state", []),
+                },
+            )
+            defer.returnValue(content)
+        except HttpResponseException as e:
+            if e.code in [400, 404]:
+                if room_version in (RoomVersions.V1, RoomVersions.V2):
+                    pass  # We'll fall through
+                else:
+                    raise Exception("Remote server is too old")
+            elif e.code == 403:
+                raise e.to_synapse_error()
+            else:
+                raise
+
+        # Didn't work, try v1 API.
+        # Note the v1 API returns a tuple of `(200, content)`
+
+        _, content = yield self.transport_layer.send_invite_v1(
+            destination=destination,
+            room_id=pdu.room_id,
+            event_id=pdu.event_id,
+            content=pdu.get_pdu_json(time_now),
+        )
+        defer.returnValue(content)
+
     def send_leave(self, destinations, pdu):
         """Sends a leave event to one of a list of homeservers.
 
@@ -785,13 +881,16 @@ class FederationClient(FederationBase):
             content=send_content,
         )
 
+        room_version = yield self.store.get_room_version(room_id)
+        format_ver = room_version_to_event_format(room_version)
+
         auth_chain = [
-            event_from_pdu_json(e)
+            event_from_pdu_json(e, format_ver)
             for e in content["auth_chain"]
         ]
 
         signed_auth = yield self._check_sigs_and_hash_and_fetch(
-            destination, auth_chain, outlier=True
+            destination, auth_chain, outlier=True, room_version=room_version,
         )
 
         signed_auth.sort(key=lambda e: e.depth)
@@ -833,13 +932,16 @@ class FederationClient(FederationBase):
                 timeout=timeout,
             )
 
+            room_version = yield self.store.get_room_version(room_id)
+            format_ver = room_version_to_event_format(room_version)
+
             events = [
-                event_from_pdu_json(e)
+                event_from_pdu_json(e, format_ver)
                 for e in content.get("events", [])
             ]
 
             signed_events = yield self._check_sigs_and_hash_and_fetch(
-                destination, events, outlier=False
+                destination, events, outlier=False, room_version=room_version,
             )
         except HttpResponseException as e:
             if not e.code == 400:
diff --git a/synapse/federation/federation_server.py b/synapse/federation/federation_server.py
index 98722ae5..aeadc9c5 100644
--- a/synapse/federation/federation_server.py
+++ b/synapse/federation/federation_server.py
@@ -25,7 +25,7 @@ from twisted.internet import defer
 from twisted.internet.abstract import isIPAddress
 from twisted.python import failure
 
-from synapse.api.constants import EventTypes
+from synapse.api.constants import EventTypes, Membership
 from synapse.api.errors import (
     AuthError,
     FederationError,
@@ -34,6 +34,7 @@ from synapse.api.errors import (
     SynapseError,
 )
 from synapse.crypto.event_signing import compute_event_signature
+from synapse.events import room_version_to_event_format
 from synapse.federation.federation_base import FederationBase, event_from_pdu_json
 from synapse.federation.persistence import TransactionActions
 from synapse.federation.units import Edu, Transaction
@@ -178,14 +179,13 @@ class FederationServer(FederationBase):
                 continue
 
             try:
-                # In future we will actually use the room version to parse the
-                # PDU into an event.
-                yield self.store.get_room_version(room_id)
+                room_version = yield self.store.get_room_version(room_id)
+                format_ver = room_version_to_event_format(room_version)
             except NotFoundError:
                 logger.info("Ignoring PDU for unknown room_id: %s", room_id)
                 continue
 
-            event = event_from_pdu_json(p)
+            event = event_from_pdu_json(p, format_ver)
             pdus_by_room.setdefault(room_id, []).append(event)
 
         pdu_results = {}
@@ -322,7 +322,7 @@ class FederationServer(FederationBase):
             if self.hs.is_mine_id(event.event_id):
                 event.signatures.update(
                     compute_event_signature(
-                        event,
+                        event.get_pdu_json(),
                         self.hs.hostname,
                         self.hs.config.signing_key[0]
                     )
@@ -369,18 +369,23 @@ class FederationServer(FederationBase):
         })
 
     @defer.inlineCallbacks
-    def on_invite_request(self, origin, content):
-        pdu = event_from_pdu_json(content)
+    def on_invite_request(self, origin, content, room_version):
+        format_ver = room_version_to_event_format(room_version)
+
+        pdu = event_from_pdu_json(content, format_ver)
         origin_host, _ = parse_server_name(origin)
         yield self.check_server_matches_acl(origin_host, pdu.room_id)
         ret_pdu = yield self.handler.on_invite_request(origin, pdu)
         time_now = self._clock.time_msec()
-        defer.returnValue((200, {"event": ret_pdu.get_pdu_json(time_now)}))
+        defer.returnValue({"event": ret_pdu.get_pdu_json(time_now)})
 
     @defer.inlineCallbacks
-    def on_send_join_request(self, origin, content):
+    def on_send_join_request(self, origin, content, room_id):
         logger.debug("on_send_join_request: content: %s", content)
-        pdu = event_from_pdu_json(content)
+
+        room_version = yield self.store.get_room_version(room_id)
+        format_ver = room_version_to_event_format(room_version)
+        pdu = event_from_pdu_json(content, format_ver)
 
         origin_host, _ = parse_server_name(origin)
         yield self.check_server_matches_acl(origin_host, pdu.room_id)
@@ -400,13 +405,22 @@ class FederationServer(FederationBase):
         origin_host, _ = parse_server_name(origin)
         yield self.check_server_matches_acl(origin_host, room_id)
         pdu = yield self.handler.on_make_leave_request(room_id, user_id)
+
+        room_version = yield self.store.get_room_version(room_id)
+
         time_now = self._clock.time_msec()
-        defer.returnValue({"event": pdu.get_pdu_json(time_now)})
+        defer.returnValue({
+            "event": pdu.get_pdu_json(time_now),
+            "room_version": room_version,
+        })
 
     @defer.inlineCallbacks
-    def on_send_leave_request(self, origin, content):
+    def on_send_leave_request(self, origin, content, room_id):
         logger.debug("on_send_leave_request: content: %s", content)
-        pdu = event_from_pdu_json(content)
+
+        room_version = yield self.store.get_room_version(room_id)
+        format_ver = room_version_to_event_format(room_version)
+        pdu = event_from_pdu_json(content, format_ver)
 
         origin_host, _ = parse_server_name(origin)
         yield self.check_server_matches_acl(origin_host, pdu.room_id)
@@ -452,13 +466,16 @@ class FederationServer(FederationBase):
             origin_host, _ = parse_server_name(origin)
             yield self.check_server_matches_acl(origin_host, room_id)
 
+            room_version = yield self.store.get_room_version(room_id)
+            format_ver = room_version_to_event_format(room_version)
+
             auth_chain = [
-                event_from_pdu_json(e)
+                event_from_pdu_json(e, format_ver)
                 for e in content["auth_chain"]
             ]
 
             signed_auth = yield self._check_sigs_and_hash_and_fetch(
-                origin, auth_chain, outlier=True
+                origin, auth_chain, outlier=True, room_version=room_version,
             )
 
             ret = yield self.handler.on_query_auth(
@@ -603,16 +620,19 @@ class FederationServer(FederationBase):
         """
         # check that it's actually being sent from a valid destination to
         # workaround bug #1753 in 0.18.5 and 0.18.6
-        if origin != get_domain_from_id(pdu.event_id):
+        if origin != get_domain_from_id(pdu.sender):
             # We continue to accept join events from any server; this is
             # necessary for the federation join dance to work correctly.
             # (When we join over federation, the "helper" server is
             # responsible for sending out the join event, rather than the
-            # origin. See bug #1893).
+            # origin. See bug #1893. This is also true for some third party
+            # invites).
             if not (
                 pdu.type == 'm.room.member' and
                 pdu.content and
-                pdu.content.get("membership", None) == 'join'
+                pdu.content.get("membership", None) in (
+                    Membership.JOIN, Membership.INVITE,
+                )
             ):
                 logger.info(
                     "Discarding PDU %s from invalid origin %s",
@@ -625,9 +645,12 @@ class FederationServer(FederationBase):
                     pdu.event_id, origin
                 )
 
+        # We've already checked that we know the room version by this point
+        room_version = yield self.store.get_room_version(pdu.room_id)
+
         # Check signature.
         try:
-            pdu = yield self._check_sigs_and_hash(pdu)
+            pdu = yield self._check_sigs_and_hash(room_version, pdu)
         except SynapseError as e:
             raise FederationError(
                 "ERROR",
diff --git a/synapse/federation/transaction_queue.py b/synapse/federation/transaction_queue.py
index fe787aba..1f0b67f5 100644
--- a/synapse/federation/transaction_queue.py
+++ b/synapse/federation/transaction_queue.py
@@ -175,7 +175,7 @@ class TransactionQueue(object):
                 def handle_event(event):
                     # Only send events for this server.
                     send_on_behalf_of = event.internal_metadata.get_send_on_behalf_of()
-                    is_mine = self.is_mine_id(event.event_id)
+                    is_mine = self.is_mine_id(event.sender)
                     if not is_mine and send_on_behalf_of is None:
                         return
 
diff --git a/synapse/federation/transport/client.py b/synapse/federation/transport/client.py
index edba5a98..8e2be218 100644
--- a/synapse/federation/transport/client.py
+++ b/synapse/federation/transport/client.py
@@ -21,7 +21,7 @@ from six.moves import urllib
 from twisted.internet import defer
 
 from synapse.api.constants import Membership
-from synapse.api.urls import FEDERATION_PREFIX as PREFIX
+from synapse.api.urls import FEDERATION_V1_PREFIX, FEDERATION_V2_PREFIX
 from synapse.util.logutils import log_function
 
 logger = logging.getLogger(__name__)
@@ -51,7 +51,7 @@ class TransportLayerClient(object):
         logger.debug("get_room_state dest=%s, room=%s",
                      destination, room_id)
 
-        path = _create_path(PREFIX, "/state/%s/", room_id)
+        path = _create_v1_path("/state/%s/", room_id)
         return self.client.get_json(
             destination, path=path, args={"event_id": event_id},
         )
@@ -73,7 +73,7 @@ class TransportLayerClient(object):
         logger.debug("get_room_state_ids dest=%s, room=%s",
                      destination, room_id)
 
-        path = _create_path(PREFIX, "/state_ids/%s/", room_id)
+        path = _create_v1_path("/state_ids/%s/", room_id)
         return self.client.get_json(
             destination, path=path, args={"event_id": event_id},
         )
@@ -95,7 +95,7 @@ class TransportLayerClient(object):
         logger.debug("get_pdu dest=%s, event_id=%s",
                      destination, event_id)
 
-        path = _create_path(PREFIX, "/event/%s/", event_id)
+        path = _create_v1_path("/event/%s/", event_id)
         return self.client.get_json(destination, path=path, timeout=timeout)
 
     @log_function
@@ -121,7 +121,7 @@ class TransportLayerClient(object):
             # TODO: raise?
             return
 
-        path = _create_path(PREFIX, "/backfill/%s/", room_id)
+        path = _create_v1_path("/backfill/%s/", room_id)
 
         args = {
             "v": event_tuples,
@@ -167,7 +167,7 @@ class TransportLayerClient(object):
         # generated by the json_data_callback.
         json_data = transaction.get_dict()
 
-        path = _create_path(PREFIX, "/send/%s/", transaction.transaction_id)
+        path = _create_v1_path("/send/%s/", transaction.transaction_id)
 
         response = yield self.client.put_json(
             transaction.destination,
@@ -184,7 +184,7 @@ class TransportLayerClient(object):
     @log_function
     def make_query(self, destination, query_type, args, retry_on_dns_fail,
                    ignore_backoff=False):
-        path = _create_path(PREFIX, "/query/%s", query_type)
+        path = _create_v1_path("/query/%s", query_type)
 
         content = yield self.client.get_json(
             destination=destination,
@@ -231,7 +231,7 @@ class TransportLayerClient(object):
                 "make_membership_event called with membership='%s', must be one of %s" %
                 (membership, ",".join(valid_memberships))
             )
-        path = _create_path(PREFIX, "/make_%s/%s/%s", membership, room_id, user_id)
+        path = _create_v1_path("/make_%s/%s/%s", membership, room_id, user_id)
 
         ignore_backoff = False
         retry_on_dns_fail = False
@@ -258,7 +258,7 @@ class TransportLayerClient(object):
     @defer.inlineCallbacks
     @log_function
     def send_join(self, destination, room_id, event_id, content):
-        path = _create_path(PREFIX, "/send_join/%s/%s", room_id, event_id)
+        path = _create_v1_path("/send_join/%s/%s", room_id, event_id)
 
         response = yield self.client.put_json(
             destination=destination,
@@ -271,7 +271,7 @@ class TransportLayerClient(object):
     @defer.inlineCallbacks
     @log_function
     def send_leave(self, destination, room_id, event_id, content):
-        path = _create_path(PREFIX, "/send_leave/%s/%s", room_id, event_id)
+        path = _create_v1_path("/send_leave/%s/%s", room_id, event_id)
 
         response = yield self.client.put_json(
             destination=destination,
@@ -289,8 +289,22 @@ class TransportLayerClient(object):
 
     @defer.inlineCallbacks
     @log_function
-    def send_invite(self, destination, room_id, event_id, content):
-        path = _create_path(PREFIX, "/invite/%s/%s", room_id, event_id)
+    def send_invite_v1(self, destination, room_id, event_id, content):
+        path = _create_v1_path("/invite/%s/%s", room_id, event_id)
+
+        response = yield self.client.put_json(
+            destination=destination,
+            path=path,
+            data=content,
+            ignore_backoff=True,
+        )
+
+        defer.returnValue(response)
+
+    @defer.inlineCallbacks
+    @log_function
+    def send_invite_v2(self, destination, room_id, event_id, content):
+        path = _create_v2_path("/invite/%s/%s", room_id, event_id)
 
         response = yield self.client.put_json(
             destination=destination,
@@ -306,7 +320,7 @@ class TransportLayerClient(object):
     def get_public_rooms(self, remote_server, limit, since_token,
                          search_filter=None, include_all_networks=False,
                          third_party_instance_id=None):
-        path = PREFIX + "/publicRooms"
+        path = _create_v1_path("/publicRooms")
 
         args = {
             "include_all_networks": "true" if include_all_networks else "false",
@@ -332,7 +346,7 @@ class TransportLayerClient(object):
     @defer.inlineCallbacks
     @log_function
     def exchange_third_party_invite(self, destination, room_id, event_dict):
-        path = _create_path(PREFIX, "/exchange_third_party_invite/%s", room_id,)
+        path = _create_v1_path("/exchange_third_party_invite/%s", room_id,)
 
         response = yield self.client.put_json(
             destination=destination,
@@ -345,7 +359,7 @@ class TransportLayerClient(object):
     @defer.inlineCallbacks
     @log_function
     def get_event_auth(self, destination, room_id, event_id):
-        path = _create_path(PREFIX, "/event_auth/%s/%s", room_id, event_id)
+        path = _create_v1_path("/event_auth/%s/%s", room_id, event_id)
 
         content = yield self.client.get_json(
             destination=destination,
@@ -357,7 +371,7 @@ class TransportLayerClient(object):
     @defer.inlineCallbacks
     @log_function
     def send_query_auth(self, destination, room_id, event_id, content):
-        path = _create_path(PREFIX, "/query_auth/%s/%s", room_id, event_id)
+        path = _create_v1_path("/query_auth/%s/%s", room_id, event_id)
 
         content = yield self.client.post_json(
             destination=destination,
@@ -392,7 +406,7 @@ class TransportLayerClient(object):
         Returns:
             A dict containg the device keys.
         """
-        path = PREFIX + "/user/keys/query"
+        path = _create_v1_path("/user/keys/query")
 
         content = yield self.client.post_json(
             destination=destination,
@@ -419,7 +433,7 @@ class TransportLayerClient(object):
         Returns:
             A dict containg the device keys.
         """
-        path = _create_path(PREFIX, "/user/devices/%s", user_id)
+        path = _create_v1_path("/user/devices/%s", user_id)
 
         content = yield self.client.get_json(
             destination=destination,
@@ -455,7 +469,7 @@ class TransportLayerClient(object):
             A dict containg the one-time keys.
         """
 
-        path = PREFIX + "/user/keys/claim"
+        path = _create_v1_path("/user/keys/claim")
 
         content = yield self.client.post_json(
             destination=destination,
@@ -469,7 +483,7 @@ class TransportLayerClient(object):
     @log_function
     def get_missing_events(self, destination, room_id, earliest_events,
                            latest_events, limit, min_depth, timeout):
-        path = _create_path(PREFIX, "/get_missing_events/%s", room_id,)
+        path = _create_v1_path("/get_missing_events/%s", room_id,)
 
         content = yield self.client.post_json(
             destination=destination,
@@ -489,7 +503,7 @@ class TransportLayerClient(object):
     def get_group_profile(self, destination, group_id, requester_user_id):
         """Get a group profile
         """
-        path = _create_path(PREFIX, "/groups/%s/profile", group_id,)
+        path = _create_v1_path("/groups/%s/profile", group_id,)
 
         return self.client.get_json(
             destination=destination,
@@ -508,7 +522,7 @@ class TransportLayerClient(object):
             requester_user_id (str)
             content (dict): The new profile of the group
         """
-        path = _create_path(PREFIX, "/groups/%s/profile", group_id,)
+        path = _create_v1_path("/groups/%s/profile", group_id,)
 
         return self.client.post_json(
             destination=destination,
@@ -522,7 +536,7 @@ class TransportLayerClient(object):
     def get_group_summary(self, destination, group_id, requester_user_id):
         """Get a group summary
         """
-        path = _create_path(PREFIX, "/groups/%s/summary", group_id,)
+        path = _create_v1_path("/groups/%s/summary", group_id,)
 
         return self.client.get_json(
             destination=destination,
@@ -535,7 +549,7 @@ class TransportLayerClient(object):
     def get_rooms_in_group(self, destination, group_id, requester_user_id):
         """Get all rooms in a group
         """
-        path = _create_path(PREFIX, "/groups/%s/rooms", group_id,)
+        path = _create_v1_path("/groups/%s/rooms", group_id,)
 
         return self.client.get_json(
             destination=destination,
@@ -548,7 +562,7 @@ class TransportLayerClient(object):
                           content):
         """Add a room to a group
         """
-        path = _create_path(PREFIX, "/groups/%s/room/%s", group_id, room_id,)
+        path = _create_v1_path("/groups/%s/room/%s", group_id, room_id,)
 
         return self.client.post_json(
             destination=destination,
@@ -562,8 +576,8 @@ class TransportLayerClient(object):
                              config_key, content):
         """Update room in group
         """
-        path = _create_path(
-            PREFIX, "/groups/%s/room/%s/config/%s",
+        path = _create_v1_path(
+            "/groups/%s/room/%s/config/%s",
             group_id, room_id, config_key,
         )
 
@@ -578,7 +592,7 @@ class TransportLayerClient(object):
     def remove_room_from_group(self, destination, group_id, requester_user_id, room_id):
         """Remove a room from a group
         """
-        path = _create_path(PREFIX, "/groups/%s/room/%s", group_id, room_id,)
+        path = _create_v1_path("/groups/%s/room/%s", group_id, room_id,)
 
         return self.client.delete_json(
             destination=destination,
@@ -591,7 +605,7 @@ class TransportLayerClient(object):
     def get_users_in_group(self, destination, group_id, requester_user_id):
         """Get users in a group
         """
-        path = _create_path(PREFIX, "/groups/%s/users", group_id,)
+        path = _create_v1_path("/groups/%s/users", group_id,)
 
         return self.client.get_json(
             destination=destination,
@@ -604,7 +618,7 @@ class TransportLayerClient(object):
     def get_invited_users_in_group(self, destination, group_id, requester_user_id):
         """Get users that have been invited to a group
         """
-        path = _create_path(PREFIX, "/groups/%s/invited_users", group_id,)
+        path = _create_v1_path("/groups/%s/invited_users", group_id,)
 
         return self.client.get_json(
             destination=destination,
@@ -617,8 +631,8 @@ class TransportLayerClient(object):
     def accept_group_invite(self, destination, group_id, user_id, content):
         """Accept a group invite
         """
-        path = _create_path(
-            PREFIX, "/groups/%s/users/%s/accept_invite",
+        path = _create_v1_path(
+            "/groups/%s/users/%s/accept_invite",
             group_id, user_id,
         )
 
@@ -633,7 +647,7 @@ class TransportLayerClient(object):
     def join_group(self, destination, group_id, user_id, content):
         """Attempts to join a group
         """
-        path = _create_path(PREFIX, "/groups/%s/users/%s/join", group_id, user_id)
+        path = _create_v1_path("/groups/%s/users/%s/join", group_id, user_id)
 
         return self.client.post_json(
             destination=destination,
@@ -646,7 +660,7 @@ class TransportLayerClient(object):
     def invite_to_group(self, destination, group_id, user_id, requester_user_id, content):
         """Invite a user to a group
         """
-        path = _create_path(PREFIX, "/groups/%s/users/%s/invite", group_id, user_id)
+        path = _create_v1_path("/groups/%s/users/%s/invite", group_id, user_id)
 
         return self.client.post_json(
             destination=destination,
@@ -662,7 +676,7 @@ class TransportLayerClient(object):
         invited.
         """
 
-        path = _create_path(PREFIX, "/groups/local/%s/users/%s/invite", group_id, user_id)
+        path = _create_v1_path("/groups/local/%s/users/%s/invite", group_id, user_id)
 
         return self.client.post_json(
             destination=destination,
@@ -676,7 +690,7 @@ class TransportLayerClient(object):
                                user_id, content):
         """Remove a user fron a group
         """
-        path = _create_path(PREFIX, "/groups/%s/users/%s/remove", group_id, user_id)
+        path = _create_v1_path("/groups/%s/users/%s/remove", group_id, user_id)
 
         return self.client.post_json(
             destination=destination,
@@ -693,7 +707,7 @@ class TransportLayerClient(object):
         kicked from the group.
         """
 
-        path = _create_path(PREFIX, "/groups/local/%s/users/%s/remove", group_id, user_id)
+        path = _create_v1_path("/groups/local/%s/users/%s/remove", group_id, user_id)
 
         return self.client.post_json(
             destination=destination,
@@ -708,7 +722,7 @@ class TransportLayerClient(object):
         the attestations
         """
 
-        path = _create_path(PREFIX, "/groups/%s/renew_attestation/%s", group_id, user_id)
+        path = _create_v1_path("/groups/%s/renew_attestation/%s", group_id, user_id)
 
         return self.client.post_json(
             destination=destination,
@@ -723,12 +737,12 @@ class TransportLayerClient(object):
         """Update a room entry in a group summary
         """
         if category_id:
-            path = _create_path(
-                PREFIX, "/groups/%s/summary/categories/%s/rooms/%s",
+            path = _create_v1_path(
+                "/groups/%s/summary/categories/%s/rooms/%s",
                 group_id, category_id, room_id,
             )
         else:
-            path = _create_path(PREFIX, "/groups/%s/summary/rooms/%s", group_id, room_id,)
+            path = _create_v1_path("/groups/%s/summary/rooms/%s", group_id, room_id,)
 
         return self.client.post_json(
             destination=destination,
@@ -744,12 +758,12 @@ class TransportLayerClient(object):
         """Delete a room entry in a group summary
         """
         if category_id:
-            path = _create_path(
-                PREFIX + "/groups/%s/summary/categories/%s/rooms/%s",
+            path = _create_v1_path(
+                "/groups/%s/summary/categories/%s/rooms/%s",
                 group_id, category_id, room_id,
             )
         else:
-            path = _create_path(PREFIX, "/groups/%s/summary/rooms/%s", group_id, room_id,)
+            path = _create_v1_path("/groups/%s/summary/rooms/%s", group_id, room_id,)
 
         return self.client.delete_json(
             destination=destination,
@@ -762,7 +776,7 @@ class TransportLayerClient(object):
     def get_group_categories(self, destination, group_id, requester_user_id):
         """Get all categories in a group
         """
-        path = _create_path(PREFIX, "/groups/%s/categories", group_id,)
+        path = _create_v1_path("/groups/%s/categories", group_id,)
 
         return self.client.get_json(
             destination=destination,
@@ -775,7 +789,7 @@ class TransportLayerClient(object):
     def get_group_category(self, destination, group_id, requester_user_id, category_id):
         """Get category info in a group
         """
-        path = _create_path(PREFIX, "/groups/%s/categories/%s", group_id, category_id,)
+        path = _create_v1_path("/groups/%s/categories/%s", group_id, category_id,)
 
         return self.client.get_json(
             destination=destination,
@@ -789,7 +803,7 @@ class TransportLayerClient(object):
                               content):
         """Update a category in a group
         """
-        path = _create_path(PREFIX, "/groups/%s/categories/%s", group_id, category_id,)
+        path = _create_v1_path("/groups/%s/categories/%s", group_id, category_id,)
 
         return self.client.post_json(
             destination=destination,
@@ -804,7 +818,7 @@ class TransportLayerClient(object):
                               category_id):
         """Delete a category in a group
         """
-        path = _create_path(PREFIX, "/groups/%s/categories/%s", group_id, category_id,)
+        path = _create_v1_path("/groups/%s/categories/%s", group_id, category_id,)
 
         return self.client.delete_json(
             destination=destination,
@@ -817,7 +831,7 @@ class TransportLayerClient(object):
     def get_group_roles(self, destination, group_id, requester_user_id):
         """Get all roles in a group
         """
-        path = _create_path(PREFIX, "/groups/%s/roles", group_id,)
+        path = _create_v1_path("/groups/%s/roles", group_id,)
 
         return self.client.get_json(
             destination=destination,
@@ -830,7 +844,7 @@ class TransportLayerClient(object):
     def get_group_role(self, destination, group_id, requester_user_id, role_id):
         """Get a roles info
         """
-        path = _create_path(PREFIX, "/groups/%s/roles/%s", group_id, role_id,)
+        path = _create_v1_path("/groups/%s/roles/%s", group_id, role_id,)
 
         return self.client.get_json(
             destination=destination,
@@ -844,7 +858,7 @@ class TransportLayerClient(object):
                           content):
         """Update a role in a group
         """
-        path = _create_path(PREFIX, "/groups/%s/roles/%s", group_id, role_id,)
+        path = _create_v1_path("/groups/%s/roles/%s", group_id, role_id,)
 
         return self.client.post_json(
             destination=destination,
@@ -858,7 +872,7 @@ class TransportLayerClient(object):
     def delete_group_role(self, destination, group_id, requester_user_id, role_id):
         """Delete a role in a group
         """
-        path = _create_path(PREFIX, "/groups/%s/roles/%s", group_id, role_id,)
+        path = _create_v1_path("/groups/%s/roles/%s", group_id, role_id,)
 
         return self.client.delete_json(
             destination=destination,
@@ -873,12 +887,12 @@ class TransportLayerClient(object):
         """Update a users entry in a group
         """
         if role_id:
-            path = _create_path(
-                PREFIX, "/groups/%s/summary/roles/%s/users/%s",
+            path = _create_v1_path(
+                "/groups/%s/summary/roles/%s/users/%s",
                 group_id, role_id, user_id,
             )
         else:
-            path = _create_path(PREFIX, "/groups/%s/summary/users/%s", group_id, user_id,)
+            path = _create_v1_path("/groups/%s/summary/users/%s", group_id, user_id,)
 
         return self.client.post_json(
             destination=destination,
@@ -893,7 +907,7 @@ class TransportLayerClient(object):
                               content):
         """Sets the join policy for a group
         """
-        path = _create_path(PREFIX, "/groups/%s/settings/m.join_policy", group_id,)
+        path = _create_v1_path("/groups/%s/settings/m.join_policy", group_id,)
 
         return self.client.put_json(
             destination=destination,
@@ -909,12 +923,12 @@ class TransportLayerClient(object):
         """Delete a users entry in a group
         """
         if role_id:
-            path = _create_path(
-                PREFIX, "/groups/%s/summary/roles/%s/users/%s",
+            path = _create_v1_path(
+                "/groups/%s/summary/roles/%s/users/%s",
                 group_id, role_id, user_id,
             )
         else:
-            path = _create_path(PREFIX, "/groups/%s/summary/users/%s", group_id, user_id,)
+            path = _create_v1_path("/groups/%s/summary/users/%s", group_id, user_id,)
 
         return self.client.delete_json(
             destination=destination,
@@ -927,7 +941,7 @@ class TransportLayerClient(object):
         """Get the groups a list of users are publicising
         """
 
-        path = PREFIX + "/get_groups_publicised"
+        path = _create_v1_path("/get_groups_publicised")
 
         content = {"user_ids": user_ids}
 
@@ -939,20 +953,43 @@ class TransportLayerClient(object):
         )
 
 
-def _create_path(prefix, path, *args):
-    """Creates a path from the prefix, path template and args. Ensures that
-    all args are url encoded.
+def _create_v1_path(path, *args):
+    """Creates a path against V1 federation API from the path template and
+    args. Ensures that all args are url encoded.
+
+    Example:
+
+        _create_v1_path("/event/%s/", event_id)
+
+    Args:
+        path (str): String template for the path
+        args: ([str]): Args to insert into path. Each arg will be url encoded
+
+    Returns:
+        str
+    """
+    return (
+        FEDERATION_V1_PREFIX
+        + path % tuple(urllib.parse.quote(arg, "") for arg in args)
+    )
+
+
+def _create_v2_path(path, *args):
+    """Creates a path against V2 federation API from the path template and
+    args. Ensures that all args are url encoded.
 
     Example:
 
-        _create_path(PREFIX, "/event/%s/", event_id)
+        _create_v2_path("/event/%s/", event_id)
 
     Args:
-        prefix (str)
         path (str): String template for the path
         args: ([str]): Args to insert into path. Each arg will be url encoded
 
     Returns:
         str
     """
-    return prefix + path % tuple(urllib.parse.quote(arg, "") for arg in args)
+    return (
+        FEDERATION_V2_PREFIX
+        + path % tuple(urllib.parse.quote(arg, "") for arg in args)
+    )
diff --git a/synapse/federation/transport/server.py b/synapse/federation/transport/server.py
index 3553f418..67ae0212 100644
--- a/synapse/federation/transport/server.py
+++ b/synapse/federation/transport/server.py
@@ -21,8 +21,9 @@ import re
 from twisted.internet import defer
 
 import synapse
+from synapse.api.constants import RoomVersions
 from synapse.api.errors import Codes, FederationDeniedError, SynapseError
-from synapse.api.urls import FEDERATION_PREFIX as PREFIX
+from synapse.api.urls import FEDERATION_V1_PREFIX, FEDERATION_V2_PREFIX
 from synapse.http.endpoint import parse_and_validate_server_name
 from synapse.http.server import JsonResource
 from synapse.http.servlet import (
@@ -227,6 +228,8 @@ class BaseFederationServlet(object):
     """
     REQUIRE_AUTH = True
 
+    PREFIX = FEDERATION_V1_PREFIX  # Allows specifying the API version
+
     def __init__(self, handler, authenticator, ratelimiter, server_name):
         self.handler = handler
         self.authenticator = authenticator
@@ -286,7 +289,7 @@ class BaseFederationServlet(object):
         return new_func
 
     def register(self, server):
-        pattern = re.compile("^" + PREFIX + self.PATH + "$")
+        pattern = re.compile("^" + self.PREFIX + self.PATH + "$")
 
         for method in ("GET", "PUT", "POST"):
             code = getattr(self, "on_%s" % (method), None)
@@ -466,7 +469,7 @@ class FederationSendLeaveServlet(BaseFederationServlet):
 
     @defer.inlineCallbacks
     def on_PUT(self, origin, content, query, room_id, event_id):
-        content = yield self.handler.on_send_leave_request(origin, content)
+        content = yield self.handler.on_send_leave_request(origin, content, room_id)
         defer.returnValue((200, content))
 
 
@@ -484,18 +487,50 @@ class FederationSendJoinServlet(BaseFederationServlet):
     def on_PUT(self, origin, content, query, context, event_id):
         # TODO(paul): assert that context/event_id parsed from path actually
         #   match those given in content
-        content = yield self.handler.on_send_join_request(origin, content)
+        content = yield self.handler.on_send_join_request(origin, content, context)
         defer.returnValue((200, content))
 
 
-class FederationInviteServlet(BaseFederationServlet):
+class FederationV1InviteServlet(BaseFederationServlet):
     PATH = "/invite/(?P<context>[^/]*)/(?P<event_id>[^/]*)"
 
     @defer.inlineCallbacks
     def on_PUT(self, origin, content, query, context, event_id):
+        # We don't get a room version, so we have to assume its EITHER v1 or
+        # v2. This is "fine" as the only difference between V1 and V2 is the
+        # state resolution algorithm, and we don't use that for processing
+        # invites
+        content = yield self.handler.on_invite_request(
+            origin, content, room_version=RoomVersions.V1,
+        )
+
+        # V1 federation API is defined to return a content of `[200, {...}]`
+        # due to a historical bug.
+        defer.returnValue((200, (200, content)))
+
+
+class FederationV2InviteServlet(BaseFederationServlet):
+    PATH = "/invite/(?P<context>[^/]*)/(?P<event_id>[^/]*)"
+
+    PREFIX = FEDERATION_V2_PREFIX
+
+    @defer.inlineCallbacks
+    def on_PUT(self, origin, content, query, context, event_id):
         # TODO(paul): assert that context/event_id parsed from path actually
         #   match those given in content
-        content = yield self.handler.on_invite_request(origin, content)
+
+        room_version = content["room_version"]
+        event = content["event"]
+        invite_room_state = content["invite_room_state"]
+
+        # Synapse expects invite_room_state to be in unsigned, as it is in v1
+        # API
+
+        event.setdefault("unsigned", {})["invite_room_state"] = invite_room_state
+
+        content = yield self.handler.on_invite_request(
+            origin, event, room_version=room_version,
+        )
         defer.returnValue((200, content))
 
 
@@ -1263,7 +1298,8 @@ FEDERATION_SERVLET_CLASSES = (
     FederationEventServlet,
     FederationSendJoinServlet,
     FederationSendLeaveServlet,
-    FederationInviteServlet,
+    FederationV1InviteServlet,
+    FederationV2InviteServlet,
     FederationQueryAuthServlet,
     FederationGetMissingEventsServlet,
     FederationEventAuthServlet,
diff --git a/synapse/handlers/acme.py b/synapse/handlers/acme.py
new file mode 100644
index 00000000..dd0b2179
--- /dev/null
+++ b/synapse/handlers/acme.py
@@ -0,0 +1,150 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+
+import attr
+from zope.interface import implementer
+
+import twisted
+import twisted.internet.error
+from twisted.internet import defer
+from twisted.python.filepath import FilePath
+from twisted.python.url import URL
+from twisted.web import server, static
+from twisted.web.resource import Resource
+
+from synapse.app import check_bind_error
+
+logger = logging.getLogger(__name__)
+
+try:
+    from txacme.interfaces import ICertificateStore
+
+    @attr.s
+    @implementer(ICertificateStore)
+    class ErsatzStore(object):
+        """
+        A store that only stores in memory.
+        """
+
+        certs = attr.ib(default=attr.Factory(dict))
+
+        def store(self, server_name, pem_objects):
+            self.certs[server_name] = [o.as_bytes() for o in pem_objects]
+            return defer.succeed(None)
+
+
+except ImportError:
+    # txacme is missing
+    pass
+
+
+class AcmeHandler(object):
+    def __init__(self, hs):
+        self.hs = hs
+        self.reactor = hs.get_reactor()
+
+    @defer.inlineCallbacks
+    def start_listening(self):
+
+        # Configure logging for txacme, if you need to debug
+        # from eliot import add_destinations
+        # from eliot.twisted import TwistedDestination
+        #
+        # add_destinations(TwistedDestination())
+
+        from txacme.challenges import HTTP01Responder
+        from txacme.service import AcmeIssuingService
+        from txacme.endpoint import load_or_create_client_key
+        from txacme.client import Client
+        from josepy.jwa import RS256
+
+        self._store = ErsatzStore()
+        responder = HTTP01Responder()
+
+        self._issuer = AcmeIssuingService(
+            cert_store=self._store,
+            client_creator=(
+                lambda: Client.from_url(
+                    reactor=self.reactor,
+                    url=URL.from_text(self.hs.config.acme_url),
+                    key=load_or_create_client_key(
+                        FilePath(self.hs.config.config_dir_path)
+                    ),
+                    alg=RS256,
+                )
+            ),
+            clock=self.reactor,
+            responders=[responder],
+        )
+
+        well_known = Resource()
+        well_known.putChild(b'acme-challenge', responder.resource)
+        responder_resource = Resource()
+        responder_resource.putChild(b'.well-known', well_known)
+        responder_resource.putChild(b'check', static.Data(b'OK', b'text/plain'))
+
+        srv = server.Site(responder_resource)
+
+        bind_addresses = self.hs.config.acme_bind_addresses
+        for host in bind_addresses:
+            logger.info(
+                "Listening for ACME requests on %s:%i", host, self.hs.config.acme_port,
+            )
+            try:
+                self.reactor.listenTCP(
+                    self.hs.config.acme_port,
+                    srv,
+                    interface=host,
+                )
+            except twisted.internet.error.CannotListenError as e:
+                check_bind_error(e, host, bind_addresses)
+
+        # Make sure we are registered to the ACME server. There's no public API
+        # for this, it is usually triggered by startService, but since we don't
+        # want it to control where we save the certificates, we have to reach in
+        # and trigger the registration machinery ourselves.
+        self._issuer._registered = False
+        yield self._issuer._ensure_registered()
+
+    @defer.inlineCallbacks
+    def provision_certificate(self):
+
+        logger.warning("Reprovisioning %s", self.hs.hostname)
+
+        try:
+            yield self._issuer.issue_cert(self.hs.hostname)
+        except Exception:
+            logger.exception("Fail!")
+            raise
+        logger.warning("Reprovisioned %s, saving.", self.hs.hostname)
+        cert_chain = self._store.certs[self.hs.hostname]
+
+        try:
+            with open(self.hs.config.tls_private_key_file, "wb") as private_key_file:
+                for x in cert_chain:
+                    if x.startswith(b"-----BEGIN RSA PRIVATE KEY-----"):
+                        private_key_file.write(x)
+
+            with open(self.hs.config.tls_certificate_file, "wb") as certificate_file:
+                for x in cert_chain:
+                    if x.startswith(b"-----BEGIN CERTIFICATE-----"):
+                        certificate_file.write(x)
+        except Exception:
+            logger.exception("Failed saving!")
+            raise
+
+        defer.returnValue(True)
diff --git a/synapse/handlers/device.py b/synapse/handlers/device.py
index 9e017116..8955cde4 100644
--- a/synapse/handlers/device.py
+++ b/synapse/handlers/device.py
@@ -532,6 +532,25 @@ class DeviceListEduUpdater(object):
 
                 stream_id = result["stream_id"]
                 devices = result["devices"]
+
+                # If the remote server has more than ~1000 devices for this user
+                # we assume that something is going horribly wrong (e.g. a bot
+                # that logs in and creates a new device every time it tries to
+                # send a message).  Maintaining lots of devices per user in the
+                # cache can cause serious performance issues as if this request
+                # takes more than 60s to complete, internal replication from the
+                # inbound federation worker to the synapse master may time out
+                # causing the inbound federation to fail and causing the remote
+                # server to retry, causing a DoS.  So in this scenario we give
+                # up on storing the total list of devices and only handle the
+                # delta instead.
+                if len(devices) > 1000:
+                    logger.warn(
+                        "Ignoring device list snapshot for %s as it has >1K devs (%d)",
+                        user_id, len(devices)
+                    )
+                    devices = []
+
                 yield self.store.update_remote_device_list_cache(
                     user_id, devices, stream_id,
                 )
diff --git a/synapse/handlers/directory.py b/synapse/handlers/directory.py
index 0699731c..6bb254f8 100644
--- a/synapse/handlers/directory.py
+++ b/synapse/handlers/directory.py
@@ -57,8 +57,8 @@ class DirectoryHandler(BaseHandler):
         # general association creation for both human users and app services
 
         for wchar in string.whitespace:
-                if wchar in room_alias.localpart:
-                    raise SynapseError(400, "Invalid characters in room alias")
+            if wchar in room_alias.localpart:
+                raise SynapseError(400, "Invalid characters in room alias")
 
         if not self.hs.is_mine(room_alias):
             raise SynapseError(400, "Room alias must be local")
diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index a3bb864b..083f2e0a 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -34,6 +34,7 @@ from synapse.api.constants import (
     EventTypes,
     Membership,
     RejectedReason,
+    RoomVersions,
 )
 from synapse.api.errors import (
     AuthError,
@@ -43,10 +44,7 @@ from synapse.api.errors import (
     StoreError,
     SynapseError,
 )
-from synapse.crypto.event_signing import (
-    add_hashes_and_signatures,
-    compute_event_signature,
-)
+from synapse.crypto.event_signing import compute_event_signature
 from synapse.events.validator import EventValidator
 from synapse.replication.http.federation import (
     ReplicationCleanRoomRestServlet,
@@ -58,7 +56,6 @@ from synapse.types import UserID, get_domain_from_id
 from synapse.util import logcontext, unwrapFirstError
 from synapse.util.async_helpers import Linearizer
 from synapse.util.distributor import user_joined_room
-from synapse.util.frozenutils import unfreeze
 from synapse.util.logutils import log_function
 from synapse.util.retryutils import NotRetryingDestination
 from synapse.visibility import filter_events_for_server
@@ -105,7 +102,7 @@ class FederationHandler(BaseHandler):
 
         self.hs = hs
 
-        self.store = hs.get_datastore()  # type: synapse.storage.DataStore
+        self.store = hs.get_datastore()
         self.federation_client = hs.get_federation_client()
         self.state_handler = hs.get_state_handler()
         self.server_name = hs.hostname
@@ -342,6 +339,8 @@ class FederationHandler(BaseHandler):
                             room_id, event_id, p,
                         )
 
+                        room_version = yield self.store.get_room_version(room_id)
+
                         with logcontext.nested_logging_context(p):
                             # note that if any of the missing prevs share missing state or
                             # auth events, the requests to fetch those events are deduped
@@ -355,7 +354,7 @@ class FederationHandler(BaseHandler):
                             # we want the state *after* p; get_state_for_room returns the
                             # state *before* p.
                             remote_event = yield self.federation_client.get_pdu(
-                                [origin], p, outlier=True,
+                                [origin], p, room_version, outlier=True,
                             )
 
                             if remote_event is None:
@@ -379,7 +378,6 @@ class FederationHandler(BaseHandler):
                             for x in remote_state:
                                 event_map[x.event_id] = x
 
-                    room_version = yield self.store.get_room_version(room_id)
                     state_map = yield resolve_events_with_store(
                         room_version, state_maps, event_map,
                         state_res_store=StateResolutionStore(self.store),
@@ -655,6 +653,8 @@ class FederationHandler(BaseHandler):
         if dest == self.server_name:
             raise SynapseError(400, "Can't backfill from self.")
 
+        room_version = yield self.store.get_room_version(room_id)
+
         events = yield self.federation_client.backfill(
             dest,
             room_id,
@@ -748,6 +748,7 @@ class FederationHandler(BaseHandler):
                             self.federation_client.get_pdu,
                             [dest],
                             event_id,
+                            room_version=room_version,
                             outlier=True,
                             timeout=10000,
                         )
@@ -1060,7 +1061,7 @@ class FederationHandler(BaseHandler):
         """
         logger.debug("Joining %s to %s", joinee, room_id)
 
-        origin, event = yield self._make_and_verify_event(
+        origin, event, event_format_version = yield self._make_and_verify_event(
             target_hosts,
             room_id,
             joinee,
@@ -1083,7 +1084,6 @@ class FederationHandler(BaseHandler):
         handled_events = set()
 
         try:
-            event = self._sign_event(event)
             # Try the host we successfully got a response to /make_join/
             # request first.
             try:
@@ -1091,7 +1091,9 @@ class FederationHandler(BaseHandler):
                 target_hosts.insert(0, origin)
             except ValueError:
                 pass
-            ret = yield self.federation_client.send_join(target_hosts, event)
+            ret = yield self.federation_client.send_join(
+                target_hosts, event, event_format_version,
+            )
 
             origin = ret["origin"]
             state = ret["state"]
@@ -1164,13 +1166,18 @@ class FederationHandler(BaseHandler):
         """
         event_content = {"membership": Membership.JOIN}
 
-        builder = self.event_builder_factory.new({
-            "type": EventTypes.Member,
-            "content": event_content,
-            "room_id": room_id,
-            "sender": user_id,
-            "state_key": user_id,
-        })
+        room_version = yield self.store.get_room_version(room_id)
+
+        builder = self.event_builder_factory.new(
+            room_version,
+            {
+                "type": EventTypes.Member,
+                "content": event_content,
+                "room_id": room_id,
+                "sender": user_id,
+                "state_key": user_id,
+            }
+        )
 
         try:
             event, context = yield self.event_creation_handler.create_new_client_event(
@@ -1182,7 +1189,9 @@ class FederationHandler(BaseHandler):
 
         # The remote hasn't signed it yet, obviously. We'll do the full checks
         # when we get the event back in `on_send_join_request`
-        yield self.auth.check_from_context(event, context, do_sig_check=False)
+        yield self.auth.check_from_context(
+            room_version, event, context, do_sig_check=False,
+        )
 
         defer.returnValue(event)
 
@@ -1287,11 +1296,11 @@ class FederationHandler(BaseHandler):
             )
 
         event.internal_metadata.outlier = True
-        event.internal_metadata.invite_from_remote = True
+        event.internal_metadata.out_of_band_membership = True
 
         event.signatures.update(
             compute_event_signature(
-                event,
+                event.get_pdu_json(),
                 self.hs.hostname,
                 self.hs.config.signing_key[0]
             )
@@ -1304,7 +1313,7 @@ class FederationHandler(BaseHandler):
 
     @defer.inlineCallbacks
     def do_remotely_reject_invite(self, target_hosts, room_id, user_id):
-        origin, event = yield self._make_and_verify_event(
+        origin, event, event_format_version = yield self._make_and_verify_event(
             target_hosts,
             room_id,
             user_id,
@@ -1313,7 +1322,7 @@ class FederationHandler(BaseHandler):
         # Mark as outlier as we don't have any state for this event; we're not
         # even in the room.
         event.internal_metadata.outlier = True
-        event = self._sign_event(event)
+        event.internal_metadata.out_of_band_membership = True
 
         # Try the host that we succesfully called /make_leave/ on first for
         # the /send_leave/ request.
@@ -1336,7 +1345,7 @@ class FederationHandler(BaseHandler):
     @defer.inlineCallbacks
     def _make_and_verify_event(self, target_hosts, room_id, user_id, membership,
                                content={}, params=None):
-        origin, pdu = yield self.federation_client.make_membership_event(
+        origin, event, format_ver = yield self.federation_client.make_membership_event(
             target_hosts,
             room_id,
             user_id,
@@ -1345,9 +1354,7 @@ class FederationHandler(BaseHandler):
             params=params,
         )
 
-        logger.debug("Got response to make_%s: %s", membership, pdu)
-
-        event = pdu
+        logger.debug("Got response to make_%s: %s", membership, event)
 
         # We should assert some things.
         # FIXME: Do this in a nicer way
@@ -1355,28 +1362,7 @@ class FederationHandler(BaseHandler):
         assert(event.user_id == user_id)
         assert(event.state_key == user_id)
         assert(event.room_id == room_id)
-        defer.returnValue((origin, event))
-
-    def _sign_event(self, event):
-        event.internal_metadata.outlier = False
-
-        builder = self.event_builder_factory.new(
-            unfreeze(event.get_pdu_json())
-        )
-
-        builder.event_id = self.event_builder_factory.create_event_id()
-        builder.origin = self.hs.hostname
-
-        if not hasattr(event, "signatures"):
-            builder.signatures = {}
-
-        add_hashes_and_signatures(
-            builder,
-            self.hs.hostname,
-            self.hs.config.signing_key[0],
-        )
-
-        return builder.build()
+        defer.returnValue((origin, event, format_ver))
 
     @defer.inlineCallbacks
     @log_function
@@ -1385,13 +1371,17 @@ class FederationHandler(BaseHandler):
         leave event for the room and return that. We do *not* persist or
         process it until the other server has signed it and sent it back.
         """
-        builder = self.event_builder_factory.new({
-            "type": EventTypes.Member,
-            "content": {"membership": Membership.LEAVE},
-            "room_id": room_id,
-            "sender": user_id,
-            "state_key": user_id,
-        })
+        room_version = yield self.store.get_room_version(room_id)
+        builder = self.event_builder_factory.new(
+            room_version,
+            {
+                "type": EventTypes.Member,
+                "content": {"membership": Membership.LEAVE},
+                "room_id": room_id,
+                "sender": user_id,
+                "state_key": user_id,
+            }
+        )
 
         event, context = yield self.event_creation_handler.create_new_client_event(
             builder=builder,
@@ -1400,7 +1390,9 @@ class FederationHandler(BaseHandler):
         try:
             # The remote hasn't signed it yet, obviously. We'll do the full checks
             # when we get the event back in `on_send_leave_request`
-            yield self.auth.check_from_context(event, context, do_sig_check=False)
+            yield self.auth.check_from_context(
+                room_version, event, context, do_sig_check=False,
+            )
         except AuthError as e:
             logger.warn("Failed to create new leave %r because %s", event, e)
             raise e
@@ -1659,6 +1651,13 @@ class FederationHandler(BaseHandler):
                 create_event = e
                 break
 
+        if create_event is None:
+            # If the state doesn't have a create event then the room is
+            # invalid, and it would fail auth checks anyway.
+            raise SynapseError(400, "No create event in state")
+
+        room_version = create_event.content.get("room_version", RoomVersions.V1)
+
         missing_auth_events = set()
         for e in itertools.chain(auth_events, state, [event]):
             for e_id in e.auth_event_ids():
@@ -1669,6 +1668,7 @@ class FederationHandler(BaseHandler):
             m_ev = yield self.federation_client.get_pdu(
                 [origin],
                 e_id,
+                room_version=room_version,
                 outlier=True,
                 timeout=10000,
             )
@@ -1687,7 +1687,7 @@ class FederationHandler(BaseHandler):
                 auth_for_e[(EventTypes.Create, "")] = create_event
 
             try:
-                self.auth.check(e, auth_events=auth_for_e)
+                self.auth.check(room_version, e, auth_events=auth_for_e)
             except SynapseError as err:
                 # we may get SynapseErrors here as well as AuthErrors. For
                 # instance, there are a couple of (ancient) events in some
@@ -1931,6 +1931,8 @@ class FederationHandler(BaseHandler):
         current_state = set(e.event_id for e in auth_events.values())
         different_auth = event_auth_events - current_state
 
+        room_version = yield self.store.get_room_version(event.room_id)
+
         if different_auth and not event.internal_metadata.is_outlier():
             # Do auth conflict res.
             logger.info("Different auth: %s", different_auth)
@@ -1955,8 +1957,6 @@ class FederationHandler(BaseHandler):
                     (d.type, d.state_key): d for d in different_events if d
                 })
 
-                room_version = yield self.store.get_room_version(event.room_id)
-
                 new_state = yield self.state_handler.resolve_events(
                     room_version,
                     [list(local_view.values()), list(remote_view.values())],
@@ -2056,7 +2056,7 @@ class FederationHandler(BaseHandler):
                 )
 
         try:
-            self.auth.check(event, auth_events=auth_events)
+            self.auth.check(room_version, event, auth_events=auth_events)
         except AuthError as e:
             logger.warn("Failed auth resolution for %r because %s", event, e)
             raise e
@@ -2279,18 +2279,26 @@ class FederationHandler(BaseHandler):
         }
 
         if (yield self.auth.check_host_in_room(room_id, self.hs.hostname)):
-            builder = self.event_builder_factory.new(event_dict)
-            EventValidator().validate_new(builder)
+            room_version = yield self.store.get_room_version(room_id)
+            builder = self.event_builder_factory.new(room_version, event_dict)
+
+            EventValidator().validate_builder(builder)
             event, context = yield self.event_creation_handler.create_new_client_event(
                 builder=builder
             )
 
             event, context = yield self.add_display_name_to_third_party_invite(
-                event_dict, event, context
+                room_version, event_dict, event, context
             )
 
+            EventValidator().validate_new(event)
+
+            # We need to tell the transaction queue to send this out, even
+            # though the sender isn't a local user.
+            event.internal_metadata.send_on_behalf_of = self.hs.hostname
+
             try:
-                yield self.auth.check_from_context(event, context)
+                yield self.auth.check_from_context(room_version, event, context)
             except AuthError as e:
                 logger.warn("Denying new third party invite %r because %s", event, e)
                 raise e
@@ -2317,23 +2325,31 @@ class FederationHandler(BaseHandler):
         Returns:
             Deferred: resolves (to None)
         """
-        builder = self.event_builder_factory.new(event_dict)
+        room_version = yield self.store.get_room_version(room_id)
+
+        # NB: event_dict has a particular specced format we might need to fudge
+        # if we change event formats too much.
+        builder = self.event_builder_factory.new(room_version, event_dict)
 
         event, context = yield self.event_creation_handler.create_new_client_event(
             builder=builder,
         )
 
         event, context = yield self.add_display_name_to_third_party_invite(
-            event_dict, event, context
+            room_version, event_dict, event, context
         )
 
         try:
-            self.auth.check_from_context(event, context)
+            self.auth.check_from_context(room_version, event, context)
         except AuthError as e:
             logger.warn("Denying third party invite %r because %s", event, e)
             raise e
         yield self._check_signature(event, context)
 
+        # We need to tell the transaction queue to send this out, even
+        # though the sender isn't a local user.
+        event.internal_metadata.send_on_behalf_of = get_domain_from_id(event.sender)
+
         # XXX we send the invite here, but send_membership_event also sends it,
         # so we end up making two requests. I think this is redundant.
         returned_invite = yield self.send_invite(origin, event)
@@ -2344,7 +2360,8 @@ class FederationHandler(BaseHandler):
         yield member_handler.send_membership_event(None, event, context)
 
     @defer.inlineCallbacks
-    def add_display_name_to_third_party_invite(self, event_dict, event, context):
+    def add_display_name_to_third_party_invite(self, room_version, event_dict,
+                                               event, context):
         key = (
             EventTypes.ThirdPartyInvite,
             event.content["third_party_invite"]["signed"]["token"]
@@ -2368,11 +2385,12 @@ class FederationHandler(BaseHandler):
             # auth checks. If we need the invite and don't have it then the
             # auth check code will explode appropriately.
 
-        builder = self.event_builder_factory.new(event_dict)
-        EventValidator().validate_new(builder)
+        builder = self.event_builder_factory.new(room_version, event_dict)
+        EventValidator().validate_builder(builder)
         event, context = yield self.event_creation_handler.create_new_client_event(
             builder=builder,
         )
+        EventValidator().validate_new(event)
         defer.returnValue((event, context))
 
     @defer.inlineCallbacks
diff --git a/synapse/handlers/identity.py b/synapse/handlers/identity.py
index 5feb3f22..39184f0e 100644
--- a/synapse/handlers/identity.py
+++ b/synapse/handlers/identity.py
@@ -167,18 +167,21 @@ class IdentityHandler(BaseHandler):
             "mxid": mxid,
             "threepid": threepid,
         }
-        headers = {}
+
         # we abuse the federation http client to sign the request, but we have to send it
         # using the normal http client since we don't want the SRV lookup and want normal
         # 'browser-like' HTTPS.
-        self.federation_http_client.sign_request(
+        auth_headers = self.federation_http_client.build_auth_headers(
             destination=None,
             method='POST',
             url_bytes='/_matrix/identity/api/v1/3pid/unbind'.encode('ascii'),
-            headers_dict=headers,
             content=content,
             destination_is=id_server,
         )
+        headers = {
+            b"Authorization": auth_headers,
+        }
+
         try:
             yield self.http_client.post_json_get_json(
                 url,
diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py
index a7cd779b..3981fe69 100644
--- a/synapse/handlers/message.py
+++ b/synapse/handlers/message.py
@@ -22,7 +22,7 @@ from canonicaljson import encode_canonical_json, json
 from twisted.internet import defer
 from twisted.internet.defer import succeed
 
-from synapse.api.constants import MAX_DEPTH, EventTypes, Membership
+from synapse.api.constants import EventTypes, Membership, RoomVersions
 from synapse.api.errors import (
     AuthError,
     Codes,
@@ -31,7 +31,6 @@ from synapse.api.errors import (
     SynapseError,
 )
 from synapse.api.urls import ConsentURIBuilder
-from synapse.crypto.event_signing import add_hashes_and_signatures
 from synapse.events.utils import serialize_event
 from synapse.events.validator import EventValidator
 from synapse.replication.http.send_event import ReplicationSendEventRestServlet
@@ -278,9 +277,17 @@ class EventCreationHandler(object):
         """
         yield self.auth.check_auth_blocking(requester.user.to_string())
 
-        builder = self.event_builder_factory.new(event_dict)
+        if event_dict["type"] == EventTypes.Create and event_dict["state_key"] == "":
+            room_version = event_dict["content"]["room_version"]
+        else:
+            try:
+                room_version = yield self.store.get_room_version(event_dict["room_id"])
+            except NotFoundError:
+                raise AuthError(403, "Unknown room")
 
-        self.validator.validate_new(builder)
+        builder = self.event_builder_factory.new(room_version, event_dict)
+
+        self.validator.validate_builder(builder)
 
         if builder.type == EventTypes.Member:
             membership = builder.content.get("membership", None)
@@ -318,6 +325,8 @@ class EventCreationHandler(object):
             prev_events_and_hashes=prev_events_and_hashes,
         )
 
+        self.validator.validate_new(event)
+
         defer.returnValue((event, context))
 
     def _is_exempt_from_privacy_policy(self, builder, requester):
@@ -535,40 +544,19 @@ class EventCreationHandler(object):
             prev_events_and_hashes = \
                 yield self.store.get_prev_events_for_room(builder.room_id)
 
-        if prev_events_and_hashes:
-            depth = max([d for _, _, d in prev_events_and_hashes]) + 1
-            # we cap depth of generated events, to ensure that they are not
-            # rejected by other servers (and so that they can be persisted in
-            # the db)
-            depth = min(depth, MAX_DEPTH)
-        else:
-            depth = 1
-
         prev_events = [
             (event_id, prev_hashes)
             for event_id, prev_hashes, _ in prev_events_and_hashes
         ]
 
-        builder.prev_events = prev_events
-        builder.depth = depth
-
-        context = yield self.state.compute_event_context(builder)
+        event = yield builder.build(
+            prev_event_ids=[p for p, _ in prev_events],
+        )
+        context = yield self.state.compute_event_context(event)
         if requester:
             context.app_service = requester.app_service
 
-        if builder.is_state():
-            builder.prev_state = yield self.store.add_event_hashes(
-                context.prev_state_events
-            )
-
-        yield self.auth.add_auth_events(builder, context)
-
-        signing_key = self.hs.config.signing_key[0]
-        add_hashes_and_signatures(
-            builder, self.server_name, signing_key
-        )
-
-        event = builder.build()
+        self.validator.validate_new(event)
 
         logger.debug(
             "Created event %s",
@@ -603,8 +591,13 @@ class EventCreationHandler(object):
             extra_users (list(UserID)): Any extra users to notify about event
         """
 
+        if event.is_state() and (event.type, event.state_key) == (EventTypes.Create, ""):
+            room_version = event.content.get("room_version", RoomVersions.V1)
+        else:
+            room_version = yield self.store.get_room_version(event.room_id)
+
         try:
-            yield self.auth.check_from_context(event, context)
+            yield self.auth.check_from_context(room_version, event, context)
         except AuthError as err:
             logger.warn("Denying new event %r because %s", event, err)
             raise err
@@ -752,7 +745,8 @@ class EventCreationHandler(object):
             auth_events = {
                 (e.type, e.state_key): e for e in auth_events.values()
             }
-            if self.auth.check_redaction(event, auth_events=auth_events):
+            room_version = yield self.store.get_room_version(event.room_id)
+            if self.auth.check_redaction(room_version, event, auth_events=auth_events):
                 original_event = yield self.store.get_event(
                     event.redacts,
                     check_redacted=False,
@@ -766,6 +760,9 @@ class EventCreationHandler(object):
                         "You don't have permission to redact events"
                     )
 
+                # We've already checked.
+                event.internal_metadata.recheck_redaction = False
+
         if event.type == EventTypes.Create:
             prev_state_ids = yield context.get_prev_state_ids(self.store)
             if prev_state_ids:
diff --git a/synapse/handlers/room.py b/synapse/handlers/room.py
index 581e96c7..13ba9291 100644
--- a/synapse/handlers/room.py
+++ b/synapse/handlers/room.py
@@ -123,9 +123,12 @@ class RoomCreationHandler(BaseHandler):
                     token_id=requester.access_token_id,
                 )
             )
-            yield self.auth.check_from_context(tombstone_event, tombstone_context)
+            old_room_version = yield self.store.get_room_version(old_room_id)
+            yield self.auth.check_from_context(
+                old_room_version, tombstone_event, tombstone_context,
+            )
 
-            yield self.clone_exiting_room(
+            yield self.clone_existing_room(
                 requester,
                 old_room_id=old_room_id,
                 new_room_id=new_room_id,
@@ -230,7 +233,7 @@ class RoomCreationHandler(BaseHandler):
         )
 
     @defer.inlineCallbacks
-    def clone_exiting_room(
+    def clone_existing_room(
             self, requester, old_room_id, new_room_id, new_room_version,
             tombstone_event_id,
     ):
@@ -262,6 +265,7 @@ class RoomCreationHandler(BaseHandler):
 
         initial_state = dict()
 
+        # Replicate relevant room events
         types_to_copy = (
             (EventTypes.JoinRules, ""),
             (EventTypes.Name, ""),
@@ -269,6 +273,7 @@ class RoomCreationHandler(BaseHandler):
             (EventTypes.RoomHistoryVisibility, ""),
             (EventTypes.GuestAccess, ""),
             (EventTypes.RoomAvatar, ""),
+            (EventTypes.Encryption, ""),
         )
 
         old_room_state_ids = yield self.store.get_filtered_current_state_ids(
diff --git a/synapse/handlers/room_list.py b/synapse/handlers/room_list.py
index dc886208..13e212d6 100644
--- a/synapse/handlers/room_list.py
+++ b/synapse/handlers/room_list.py
@@ -73,8 +73,14 @@ class RoomListHandler(BaseHandler):
             # We explicitly don't bother caching searches or requests for
             # appservice specific lists.
             logger.info("Bypassing cache as search request.")
+
+            # XXX: Quick hack to stop room directory queries taking too long.
+            # Timeout request after 60s. Probably want a more fundamental
+            # solution at some point
+            timeout = self.clock.time() + 60
             return self._get_public_room_list(
-                limit, since_token, search_filter, network_tuple=network_tuple,
+                limit, since_token, search_filter,
+                network_tuple=network_tuple, timeout=timeout,
             )
 
         key = (limit, since_token, network_tuple)
@@ -87,7 +93,8 @@ class RoomListHandler(BaseHandler):
     @defer.inlineCallbacks
     def _get_public_room_list(self, limit=None, since_token=None,
                               search_filter=None,
-                              network_tuple=EMPTY_THIRD_PARTY_ID,):
+                              network_tuple=EMPTY_THIRD_PARTY_ID,
+                              timeout=None,):
         if since_token and since_token != "END":
             since_token = RoomListNextBatch.from_token(since_token)
         else:
@@ -202,6 +209,9 @@ class RoomListHandler(BaseHandler):
 
         chunk = []
         for i in range(0, len(rooms_to_scan), step):
+            if timeout and self.clock.time() > timeout:
+                raise Exception("Timed out searching room directory")
+
             batch = rooms_to_scan[i:i + step]
             logger.info("Processing %i rooms for result", len(batch))
             yield concurrently_execute(
diff --git a/synapse/handlers/room_member.py b/synapse/handlers/room_member.py
index 07fd3e82..2beffdf4 100644
--- a/synapse/handlers/room_member.py
+++ b/synapse/handlers/room_member.py
@@ -63,7 +63,7 @@ class RoomMemberHandler(object):
         self.directory_handler = hs.get_handlers().directory_handler
         self.registration_handler = hs.get_handlers().registration_handler
         self.profile_handler = hs.get_profile_handler()
-        self.event_creation_hander = hs.get_event_creation_handler()
+        self.event_creation_handler = hs.get_event_creation_handler()
 
         self.member_linearizer = Linearizer(name="member")
 
@@ -161,6 +161,8 @@ class RoomMemberHandler(object):
         ratelimit=True,
         content=None,
     ):
+        user_id = target.to_string()
+
         if content is None:
             content = {}
 
@@ -168,14 +170,14 @@ class RoomMemberHandler(object):
         if requester.is_guest:
             content["kind"] = "guest"
 
-        event, context = yield self.event_creation_hander.create_event(
+        event, context = yield self.event_creation_handler.create_event(
             requester,
             {
                 "type": EventTypes.Member,
                 "content": content,
                 "room_id": room_id,
                 "sender": requester.user.to_string(),
-                "state_key": target.to_string(),
+                "state_key": user_id,
 
                 # For backwards compatibility:
                 "membership": membership,
@@ -186,14 +188,14 @@ class RoomMemberHandler(object):
         )
 
         # Check if this event matches the previous membership event for the user.
-        duplicate = yield self.event_creation_hander.deduplicate_state_event(
+        duplicate = yield self.event_creation_handler.deduplicate_state_event(
             event, context,
         )
         if duplicate is not None:
             # Discard the new event since this membership change is a no-op.
             defer.returnValue(duplicate)
 
-        yield self.event_creation_hander.handle_new_client_event(
+        yield self.event_creation_handler.handle_new_client_event(
             requester,
             event,
             context,
@@ -204,12 +206,12 @@ class RoomMemberHandler(object):
         prev_state_ids = yield context.get_prev_state_ids(self.store)
 
         prev_member_event_id = prev_state_ids.get(
-            (EventTypes.Member, target.to_string()),
+            (EventTypes.Member, user_id),
             None
         )
 
         if event.membership == Membership.JOIN:
-            # Only fire user_joined_room if the user has acutally joined the
+            # Only fire user_joined_room if the user has actually joined the
             # room. Don't bother if the user is just changing their profile
             # info.
             newly_joined = True
@@ -218,6 +220,18 @@ class RoomMemberHandler(object):
                 newly_joined = prev_member_event.membership != Membership.JOIN
             if newly_joined:
                 yield self._user_joined_room(target, room_id)
+
+            # Copy over direct message status and room tags if this is a join
+            # on an upgraded room
+
+            # Check if this is an upgraded room
+            predecessor = yield self.store.get_room_predecessor(room_id)
+
+            if predecessor:
+                # It is an upgraded room. Copy over old tags
+                self.copy_room_tags_and_direct_to_room(
+                    predecessor["room_id"], room_id, user_id,
+                )
         elif event.membership == Membership.LEAVE:
             if prev_member_event_id:
                 prev_member_event = yield self.store.get_event(prev_member_event_id)
@@ -227,6 +241,55 @@ class RoomMemberHandler(object):
         defer.returnValue(event)
 
     @defer.inlineCallbacks
+    def copy_room_tags_and_direct_to_room(
+        self,
+        old_room_id,
+        new_room_id,
+        user_id,
+    ):
+        """Copies the tags and direct room state from one room to another.
+
+        Args:
+            old_room_id (str)
+            new_room_id (str)
+            user_id (str)
+
+        Returns:
+            Deferred[None]
+        """
+        # Retrieve user account data for predecessor room
+        user_account_data, _ = yield self.store.get_account_data_for_user(
+            user_id,
+        )
+
+        # Copy direct message state if applicable
+        direct_rooms = user_account_data.get("m.direct", {})
+
+        # Check which key this room is under
+        if isinstance(direct_rooms, dict):
+            for key, room_id_list in direct_rooms.items():
+                if old_room_id in room_id_list and new_room_id not in room_id_list:
+                    # Add new room_id to this key
+                    direct_rooms[key].append(new_room_id)
+
+                    # Save back to user's m.direct account data
+                    yield self.store.add_account_data_for_user(
+                        user_id, "m.direct", direct_rooms,
+                    )
+                    break
+
+        # Copy room tags if applicable
+        room_tags = yield self.store.get_tags_for_room(
+            user_id, old_room_id,
+        )
+
+        # Copy each room tag to the new room
+        for tag, tag_content in room_tags.items():
+            yield self.store.add_tag_to_room(
+                user_id, new_room_id, tag, tag_content
+            )
+
+    @defer.inlineCallbacks
     def update_membership(
             self,
             requester,
@@ -493,7 +556,7 @@ class RoomMemberHandler(object):
         else:
             requester = synapse.types.create_requester(target_user)
 
-        prev_event = yield self.event_creation_hander.deduplicate_state_event(
+        prev_event = yield self.event_creation_handler.deduplicate_state_event(
             event, context,
         )
         if prev_event is not None:
@@ -513,7 +576,7 @@ class RoomMemberHandler(object):
             if is_blocked:
                 raise SynapseError(403, "This room has been blocked on this server")
 
-        yield self.event_creation_hander.handle_new_client_event(
+        yield self.event_creation_handler.handle_new_client_event(
             requester,
             event,
             context,
@@ -527,7 +590,7 @@ class RoomMemberHandler(object):
         )
 
         if event.membership == Membership.JOIN:
-            # Only fire user_joined_room if the user has acutally joined the
+            # Only fire user_joined_room if the user has actually joined the
             # room. Don't bother if the user is just changing their profile
             # info.
             newly_joined = True
@@ -755,7 +818,7 @@ class RoomMemberHandler(object):
             )
         )
 
-        yield self.event_creation_hander.create_and_send_nonmember_event(
+        yield self.event_creation_handler.create_and_send_nonmember_event(
             requester,
             {
                 "type": EventTypes.ThirdPartyInvite,
@@ -877,7 +940,8 @@ class RoomMemberHandler(object):
         # first member event?
         create_event_id = current_state_ids.get(("m.room.create", ""))
         if len(current_state_ids) == 1 and create_event_id:
-            defer.returnValue(self.hs.is_mine_id(create_event_id))
+            # We can only get here if we're in the process of creating the room
+            defer.returnValue(True)
 
         for etype, state_key in current_state_ids:
             if etype != EventTypes.Member or not self.hs.is_mine_id(state_key):
diff --git a/synapse/handlers/search.py b/synapse/handlers/search.py
index ec936bbb..49c43931 100644
--- a/synapse/handlers/search.py
+++ b/synapse/handlers/search.py
@@ -38,6 +38,41 @@ class SearchHandler(BaseHandler):
         super(SearchHandler, self).__init__(hs)
 
     @defer.inlineCallbacks
+    def get_old_rooms_from_upgraded_room(self, room_id):
+        """Retrieves room IDs of old rooms in the history of an upgraded room.
+
+        We do so by checking the m.room.create event of the room for a
+        `predecessor` key. If it exists, we add the room ID to our return
+        list and then check that room for a m.room.create event and so on
+        until we can no longer find any more previous rooms.
+
+        The full list of all found rooms in then returned.
+
+        Args:
+            room_id (str): id of the room to search through.
+
+        Returns:
+            Deferred[iterable[unicode]]: predecessor room ids
+        """
+
+        historical_room_ids = []
+
+        while True:
+            predecessor = yield self.store.get_room_predecessor(room_id)
+
+            # If no predecessor, assume we've hit a dead end
+            if not predecessor:
+                break
+
+            # Add predecessor's room ID
+            historical_room_ids.append(predecessor["room_id"])
+
+            # Scan through the old room for further predecessors
+            room_id = predecessor["room_id"]
+
+        defer.returnValue(historical_room_ids)
+
+    @defer.inlineCallbacks
     def search(self, user, content, batch=None):
         """Performs a full text search for a user.
 
@@ -137,6 +172,18 @@ class SearchHandler(BaseHandler):
         )
         room_ids = set(r.room_id for r in rooms)
 
+        # If doing a subset of all rooms seearch, check if any of the rooms
+        # are from an upgraded room, and search their contents as well
+        if search_filter.rooms:
+            historical_room_ids = []
+            for room_id in search_filter.rooms:
+                # Add any previous rooms to the search if they exist
+                ids = yield self.get_old_rooms_from_upgraded_room(room_id)
+                historical_room_ids += ids
+
+            # Prevent any historical events from being filtered
+            search_filter = search_filter.with_room_ids(historical_room_ids)
+
         room_ids = search_filter.filter_rooms(room_ids)
 
         if batch_group == "room_id":
diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py
index f7f768f7..bd97241a 100644
--- a/synapse/handlers/sync.py
+++ b/synapse/handlers/sync.py
@@ -895,14 +895,17 @@ class SyncHandler(object):
         Returns:
             Deferred(SyncResult)
         """
-        logger.info("Calculating sync response for %r", sync_config.user)
-
         # NB: The now_token gets changed by some of the generate_sync_* methods,
         # this is due to some of the underlying streams not supporting the ability
         # to query up to a given point.
         # Always use the `now_token` in `SyncResultBuilder`
         now_token = yield self.event_sources.get_current_token()
 
+        logger.info(
+            "Calculating sync response for %r between %s and %s",
+            sync_config.user, since_token, now_token,
+        )
+
         user_id = sync_config.user.to_string()
         app_service = self.store.get_app_service_by_user_id(user_id)
         if app_service:
@@ -1390,6 +1393,12 @@ class SyncHandler(object):
         room_entries = []
         invited = []
         for room_id, events in iteritems(mem_change_events_by_room_id):
+            logger.info(
+                "Membership changes in %s: [%s]",
+                room_id,
+                ", ".join(("%s (%s)" % (e.event_id, e.membership) for e in events)),
+            )
+
             non_joins = [e for e in events if e.membership != Membership.JOIN]
             has_join = len(non_joins) != len(events)
 
@@ -1473,10 +1482,22 @@ class SyncHandler(object):
                 if since_token and since_token.is_after(leave_token):
                     continue
 
+                # If this is an out of band message, like a remote invite
+                # rejection, we include it in the recents batch. Otherwise, we
+                # let _load_filtered_recents handle fetching the correct
+                # batches.
+                #
+                # This is all screaming out for a refactor, as the logic here is
+                # subtle and the moving parts numerous.
+                if leave_event.internal_metadata.is_out_of_band_membership():
+                    batch_events = [leave_event]
+                else:
+                    batch_events = None
+
                 room_entries.append(RoomSyncResultBuilder(
                     room_id=room_id,
                     rtype="archived",
-                    events=None,
+                    events=batch_events,
                     newly_joined=room_id in newly_joined_rooms,
                     full_state=False,
                     since_token=since_token,
diff --git a/synapse/handlers/user_directory.py b/synapse/handlers/user_directory.py
index 3c409993..120815b0 100644
--- a/synapse/handlers/user_directory.py
+++ b/synapse/handlers/user_directory.py
@@ -19,6 +19,7 @@ from six import iteritems
 
 from twisted.internet import defer
 
+import synapse.metrics
 from synapse.api.constants import EventTypes, JoinRules, Membership
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.storage.roommember import ProfileInfo
@@ -163,6 +164,11 @@ class UserDirectoryHandler(object):
                 yield self._handle_deltas(deltas)
 
                 self.pos = deltas[-1]["stream_id"]
+
+                # Expose current event processing position to prometheus
+                synapse.metrics.event_processing_positions.labels(
+                    "user_dir").set(self.pos)
+
                 yield self.store.update_user_directory_stream_pos(self.pos)
 
     @defer.inlineCallbacks
diff --git a/synapse/http/client.py b/synapse/http/client.py
index afcf698b..47a1f82f 100644
--- a/synapse/http/client.py
+++ b/synapse/http/client.py
@@ -333,9 +333,10 @@ class SimpleHttpClient(object):
             "POST", uri, headers=Headers(actual_headers), data=query_bytes
         )
 
+        body = yield make_deferred_yieldable(readBody(response))
+
         if 200 <= response.code < 300:
-            body = yield make_deferred_yieldable(treq.json_content(response))
-            defer.returnValue(body)
+            defer.returnValue(json.loads(body))
         else:
             raise HttpResponseException(response.code, response.phrase, body)
 
diff --git a/synapse/http/endpoint.py b/synapse/http/endpoint.py
index f86a0b62..cd79ebab 100644
--- a/synapse/http/endpoint.py
+++ b/synapse/http/endpoint.py
@@ -12,30 +12,11 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-import collections
 import logging
-import random
 import re
-import time
-
-from twisted.internet import defer
-from twisted.internet.endpoints import HostnameEndpoint, wrapClientTLS
-from twisted.internet.error import ConnectError
-from twisted.names import client, dns
-from twisted.names.error import DNSNameError, DomainError
 
 logger = logging.getLogger(__name__)
 
-SERVER_CACHE = {}
-
-# our record of an individual server which can be tried to reach a destination.
-#
-# "host" is the hostname acquired from the SRV record. Except when there's
-# no SRV record, in which case it is the original hostname.
-_Server = collections.namedtuple(
-    "_Server", "priority weight host port expires"
-)
-
 
 def parse_server_name(server_name):
     """Split a server name into host/port parts.
@@ -100,264 +81,3 @@ def parse_and_validate_server_name(server_name):
         ))
 
     return host, port
-
-
-def matrix_federation_endpoint(reactor, destination, tls_client_options_factory=None,
-                               timeout=None):
-    """Construct an endpoint for the given matrix destination.
-
-    Args:
-        reactor: Twisted reactor.
-        destination (unicode): The name of the server to connect to.
-        tls_client_options_factory
-            (synapse.crypto.context_factory.ClientTLSOptionsFactory):
-            Factory which generates TLS options for client connections.
-        timeout (int): connection timeout in seconds
-    """
-
-    domain, port = parse_server_name(destination)
-
-    endpoint_kw_args = {}
-
-    if timeout is not None:
-        endpoint_kw_args.update(timeout=timeout)
-
-    if tls_client_options_factory is None:
-        transport_endpoint = HostnameEndpoint
-        default_port = 8008
-    else:
-        # the SNI string should be the same as the Host header, minus the port.
-        # as per https://github.com/matrix-org/synapse/issues/2525#issuecomment-336896777,
-        # the Host header and SNI should therefore be the server_name of the remote
-        # server.
-        tls_options = tls_client_options_factory.get_options(domain)
-
-        def transport_endpoint(reactor, host, port, timeout):
-            return wrapClientTLS(
-                tls_options,
-                HostnameEndpoint(reactor, host, port, timeout=timeout),
-            )
-        default_port = 8448
-
-    if port is None:
-        return _WrappingEndpointFac(SRVClientEndpoint(
-            reactor, "matrix", domain, protocol="tcp",
-            default_port=default_port, endpoint=transport_endpoint,
-            endpoint_kw_args=endpoint_kw_args
-        ), reactor)
-    else:
-        return _WrappingEndpointFac(transport_endpoint(
-            reactor, domain, port, **endpoint_kw_args
-        ), reactor)
-
-
-class _WrappingEndpointFac(object):
-    def __init__(self, endpoint_fac, reactor):
-        self.endpoint_fac = endpoint_fac
-        self.reactor = reactor
-
-    @defer.inlineCallbacks
-    def connect(self, protocolFactory):
-        conn = yield self.endpoint_fac.connect(protocolFactory)
-        conn = _WrappedConnection(conn, self.reactor)
-        defer.returnValue(conn)
-
-
-class _WrappedConnection(object):
-    """Wraps a connection and calls abort on it if it hasn't seen any action
-    for 2.5-3 minutes.
-    """
-    __slots__ = ["conn", "last_request"]
-
-    def __init__(self, conn, reactor):
-        object.__setattr__(self, "conn", conn)
-        object.__setattr__(self, "last_request", time.time())
-        self._reactor = reactor
-
-    def __getattr__(self, name):
-        return getattr(self.conn, name)
-
-    def __setattr__(self, name, value):
-        setattr(self.conn, name, value)
-
-    def _time_things_out_maybe(self):
-        # We use a slightly shorter timeout here just in case the callLater is
-        # triggered early. Paranoia ftw.
-        # TODO: Cancel the previous callLater rather than comparing time.time()?
-        if time.time() - self.last_request >= 2.5 * 60:
-            self.abort()
-            # Abort the underlying TLS connection. The abort() method calls
-            # loseConnection() on the TLS connection which tries to
-            # shutdown the connection cleanly. We call abortConnection()
-            # since that will promptly close the TLS connection.
-            #
-            # In Twisted >18.4; the TLS connection will be None if it has closed
-            # which will make abortConnection() throw. Check that the TLS connection
-            # is not None before trying to close it.
-            if self.transport.getHandle() is not None:
-                self.transport.abortConnection()
-
-    def request(self, request):
-        self.last_request = time.time()
-
-        # Time this connection out if we haven't send a request in the last
-        # N minutes
-        # TODO: Cancel the previous callLater?
-        self._reactor.callLater(3 * 60, self._time_things_out_maybe)
-
-        d = self.conn.request(request)
-
-        def update_request_time(res):
-            self.last_request = time.time()
-            # TODO: Cancel the previous callLater?
-            self._reactor.callLater(3 * 60, self._time_things_out_maybe)
-            return res
-
-        d.addCallback(update_request_time)
-
-        return d
-
-
-class SRVClientEndpoint(object):
-    """An endpoint which looks up SRV records for a service.
-    Cycles through the list of servers starting with each call to connect
-    picking the next server.
-    Implements twisted.internet.interfaces.IStreamClientEndpoint.
-    """
-
-    def __init__(self, reactor, service, domain, protocol="tcp",
-                 default_port=None, endpoint=HostnameEndpoint,
-                 endpoint_kw_args={}):
-        self.reactor = reactor
-        self.service_name = "_%s._%s.%s" % (service, protocol, domain)
-
-        if default_port is not None:
-            self.default_server = _Server(
-                host=domain,
-                port=default_port,
-                priority=0,
-                weight=0,
-                expires=0,
-            )
-        else:
-            self.default_server = None
-
-        self.endpoint = endpoint
-        self.endpoint_kw_args = endpoint_kw_args
-
-        self.servers = None
-        self.used_servers = None
-
-    @defer.inlineCallbacks
-    def fetch_servers(self):
-        self.used_servers = []
-        self.servers = yield resolve_service(self.service_name)
-
-    def pick_server(self):
-        if not self.servers:
-            if self.used_servers:
-                self.servers = self.used_servers
-                self.used_servers = []
-                self.servers.sort()
-            elif self.default_server:
-                return self.default_server
-            else:
-                raise ConnectError(
-                    "No server available for %s" % self.service_name
-                )
-
-        # look for all servers with the same priority
-        min_priority = self.servers[0].priority
-        weight_indexes = list(
-            (index, server.weight + 1)
-            for index, server in enumerate(self.servers)
-            if server.priority == min_priority
-        )
-
-        total_weight = sum(weight for index, weight in weight_indexes)
-        target_weight = random.randint(0, total_weight)
-        for index, weight in weight_indexes:
-            target_weight -= weight
-            if target_weight <= 0:
-                server = self.servers[index]
-                # XXX: this looks totally dubious:
-                #
-                # (a) we never reuse a server until we have been through
-                #     all of the servers at the same priority, so if the
-                #     weights are A: 100, B:1, we always do ABABAB instead of
-                #     AAAA...AAAB (approximately).
-                #
-                # (b) After using all the servers at the lowest priority,
-                #     we move onto the next priority. We should only use the
-                #     second priority if servers at the top priority are
-                #     unreachable.
-                #
-                del self.servers[index]
-                self.used_servers.append(server)
-                return server
-
-    @defer.inlineCallbacks
-    def connect(self, protocolFactory):
-        if self.servers is None:
-            yield self.fetch_servers()
-        server = self.pick_server()
-        logger.info("Connecting to %s:%s", server.host, server.port)
-        endpoint = self.endpoint(
-            self.reactor, server.host, server.port, **self.endpoint_kw_args
-        )
-        connection = yield endpoint.connect(protocolFactory)
-        defer.returnValue(connection)
-
-
-@defer.inlineCallbacks
-def resolve_service(service_name, dns_client=client, cache=SERVER_CACHE, clock=time):
-    cache_entry = cache.get(service_name, None)
-    if cache_entry:
-        if all(s.expires > int(clock.time()) for s in cache_entry):
-            servers = list(cache_entry)
-            defer.returnValue(servers)
-
-    servers = []
-
-    try:
-        try:
-            answers, _, _ = yield dns_client.lookupService(service_name)
-        except DNSNameError:
-            defer.returnValue([])
-
-        if (len(answers) == 1
-                and answers[0].type == dns.SRV
-                and answers[0].payload
-                and answers[0].payload.target == dns.Name(b'.')):
-            raise ConnectError("Service %s unavailable" % service_name)
-
-        for answer in answers:
-            if answer.type != dns.SRV or not answer.payload:
-                continue
-
-            payload = answer.payload
-
-            servers.append(_Server(
-                host=str(payload.target),
-                port=int(payload.port),
-                priority=int(payload.priority),
-                weight=int(payload.weight),
-                expires=int(clock.time()) + answer.ttl,
-            ))
-
-        servers.sort()
-        cache[service_name] = list(servers)
-    except DomainError as e:
-        # We failed to resolve the name (other than a NameError)
-        # Try something in the cache, else rereaise
-        cache_entry = cache.get(service_name, None)
-        if cache_entry:
-            logger.warn(
-                "Failed to resolve %r, falling back to cache. %r",
-                service_name, e
-            )
-            servers = list(cache_entry)
-        else:
-            raise e
-
-    defer.returnValue(servers)
diff --git a/synapse/http/federation/__init__.py b/synapse/http/federation/__init__.py
new file mode 100644
index 00000000..1453d045
--- /dev/null
+++ b/synapse/http/federation/__init__.py
@@ -0,0 +1,14 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
diff --git a/synapse/http/federation/matrix_federation_agent.py b/synapse/http/federation/matrix_federation_agent.py
new file mode 100644
index 00000000..384d8a37
--- /dev/null
+++ b/synapse/http/federation/matrix_federation_agent.py
@@ -0,0 +1,452 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import json
+import logging
+import random
+import time
+
+import attr
+from netaddr import IPAddress
+from zope.interface import implementer
+
+from twisted.internet import defer
+from twisted.internet.endpoints import HostnameEndpoint, wrapClientTLS
+from twisted.internet.interfaces import IStreamClientEndpoint
+from twisted.web.client import URI, Agent, HTTPConnectionPool, RedirectAgent, readBody
+from twisted.web.http import stringToDatetime
+from twisted.web.http_headers import Headers
+from twisted.web.iweb import IAgent
+
+from synapse.http.federation.srv_resolver import SrvResolver, pick_server_from_list
+from synapse.util import Clock
+from synapse.util.caches.ttlcache import TTLCache
+from synapse.util.logcontext import make_deferred_yieldable
+from synapse.util.metrics import Measure
+
+# period to cache .well-known results for by default
+WELL_KNOWN_DEFAULT_CACHE_PERIOD = 24 * 3600
+
+# jitter to add to the .well-known default cache ttl
+WELL_KNOWN_DEFAULT_CACHE_PERIOD_JITTER = 10 * 60
+
+# period to cache failure to fetch .well-known for
+WELL_KNOWN_INVALID_CACHE_PERIOD = 1 * 3600
+
+# cap for .well-known cache period
+WELL_KNOWN_MAX_CACHE_PERIOD = 48 * 3600
+
+logger = logging.getLogger(__name__)
+well_known_cache = TTLCache('well-known')
+
+
+@implementer(IAgent)
+class MatrixFederationAgent(object):
+    """An Agent-like thing which provides a `request` method which will look up a matrix
+    server and send an HTTP request to it.
+
+    Doesn't implement any retries. (Those are done in MatrixFederationHttpClient.)
+
+    Args:
+        reactor (IReactor): twisted reactor to use for underlying requests
+
+        tls_client_options_factory (ClientTLSOptionsFactory|None):
+            factory to use for fetching client tls options, or none to disable TLS.
+
+        _well_known_tls_policy (IPolicyForHTTPS|None):
+            TLS policy to use for fetching .well-known files. None to use a default
+            (browser-like) implementation.
+
+        srv_resolver (SrvResolver|None):
+            SRVResolver impl to use for looking up SRV records. None to use a default
+            implementation.
+    """
+
+    def __init__(
+        self, reactor, tls_client_options_factory,
+        _well_known_tls_policy=None,
+        _srv_resolver=None,
+        _well_known_cache=well_known_cache,
+    ):
+        self._reactor = reactor
+        self._clock = Clock(reactor)
+
+        self._tls_client_options_factory = tls_client_options_factory
+        if _srv_resolver is None:
+            _srv_resolver = SrvResolver()
+        self._srv_resolver = _srv_resolver
+
+        self._pool = HTTPConnectionPool(reactor)
+        self._pool.retryAutomatically = False
+        self._pool.maxPersistentPerHost = 5
+        self._pool.cachedConnectionTimeout = 2 * 60
+
+        agent_args = {}
+        if _well_known_tls_policy is not None:
+            # the param is called 'contextFactory', but actually passing a
+            # contextfactory is deprecated, and it expects an IPolicyForHTTPS.
+            agent_args['contextFactory'] = _well_known_tls_policy
+        _well_known_agent = RedirectAgent(
+            Agent(self._reactor, pool=self._pool, **agent_args),
+        )
+        self._well_known_agent = _well_known_agent
+
+        # our cache of .well-known lookup results, mapping from server name
+        # to delegated name. The values can be:
+        #   `bytes`:     a valid server-name
+        #   `None`:      there is no (valid) .well-known here
+        self._well_known_cache = _well_known_cache
+
+    @defer.inlineCallbacks
+    def request(self, method, uri, headers=None, bodyProducer=None):
+        """
+        Args:
+            method (bytes): HTTP method: GET/POST/etc
+
+            uri (bytes): Absolute URI to be retrieved
+
+            headers (twisted.web.http_headers.Headers|None):
+                HTTP headers to send with the request, or None to
+                send no extra headers.
+
+            bodyProducer (twisted.web.iweb.IBodyProducer|None):
+                An object which can generate bytes to make up the
+                body of this request (for example, the properly encoded contents of
+                a file for a file upload).  Or None if the request is to have
+                no body.
+
+        Returns:
+            Deferred[twisted.web.iweb.IResponse]:
+                fires when the header of the response has been received (regardless of the
+                response status code). Fails if there is any problem which prevents that
+                response from being received (including problems that prevent the request
+                from being sent).
+        """
+        parsed_uri = URI.fromBytes(uri, defaultPort=-1)
+        res = yield self._route_matrix_uri(parsed_uri)
+
+        # set up the TLS connection params
+        #
+        # XXX disabling TLS is really only supported here for the benefit of the
+        # unit tests. We should make the UTs cope with TLS rather than having to make
+        # the code support the unit tests.
+        if self._tls_client_options_factory is None:
+            tls_options = None
+        else:
+            tls_options = self._tls_client_options_factory.get_options(
+                res.tls_server_name.decode("ascii")
+            )
+
+        # make sure that the Host header is set correctly
+        if headers is None:
+            headers = Headers()
+        else:
+            headers = headers.copy()
+
+        if not headers.hasHeader(b'host'):
+            headers.addRawHeader(b'host', res.host_header)
+
+        class EndpointFactory(object):
+            @staticmethod
+            def endpointForURI(_uri):
+                ep = LoggingHostnameEndpoint(
+                    self._reactor, res.target_host, res.target_port,
+                )
+                if tls_options is not None:
+                    ep = wrapClientTLS(tls_options, ep)
+                return ep
+
+        agent = Agent.usingEndpointFactory(self._reactor, EndpointFactory(), self._pool)
+        res = yield make_deferred_yieldable(
+            agent.request(method, uri, headers, bodyProducer)
+        )
+        defer.returnValue(res)
+
+    @defer.inlineCallbacks
+    def _route_matrix_uri(self, parsed_uri, lookup_well_known=True):
+        """Helper for `request`: determine the routing for a Matrix URI
+
+        Args:
+            parsed_uri (twisted.web.client.URI): uri to route. Note that it should be
+                parsed with URI.fromBytes(uri, defaultPort=-1) to set the `port` to -1
+                if there is no explicit port given.
+
+            lookup_well_known (bool): True if we should look up the .well-known file if
+                there is no SRV record.
+
+        Returns:
+            Deferred[_RoutingResult]
+        """
+        # check for an IP literal
+        try:
+            ip_address = IPAddress(parsed_uri.host.decode("ascii"))
+        except Exception:
+            # not an IP address
+            ip_address = None
+
+        if ip_address:
+            port = parsed_uri.port
+            if port == -1:
+                port = 8448
+            defer.returnValue(_RoutingResult(
+                host_header=parsed_uri.netloc,
+                tls_server_name=parsed_uri.host,
+                target_host=parsed_uri.host,
+                target_port=port,
+            ))
+
+        if parsed_uri.port != -1:
+            # there is an explicit port
+            defer.returnValue(_RoutingResult(
+                host_header=parsed_uri.netloc,
+                tls_server_name=parsed_uri.host,
+                target_host=parsed_uri.host,
+                target_port=parsed_uri.port,
+            ))
+
+        if lookup_well_known:
+            # try a .well-known lookup
+            well_known_server = yield self._get_well_known(parsed_uri.host)
+
+            if well_known_server:
+                # if we found a .well-known, start again, but don't do another
+                # .well-known lookup.
+
+                # parse the server name in the .well-known response into host/port.
+                # (This code is lifted from twisted.web.client.URI.fromBytes).
+                if b':' in well_known_server:
+                    well_known_host, well_known_port = well_known_server.rsplit(b':', 1)
+                    try:
+                        well_known_port = int(well_known_port)
+                    except ValueError:
+                        # the part after the colon could not be parsed as an int
+                        # - we assume it is an IPv6 literal with no port (the closing
+                        # ']' stops it being parsed as an int)
+                        well_known_host, well_known_port = well_known_server, -1
+                else:
+                    well_known_host, well_known_port = well_known_server, -1
+
+                new_uri = URI(
+                    scheme=parsed_uri.scheme,
+                    netloc=well_known_server,
+                    host=well_known_host,
+                    port=well_known_port,
+                    path=parsed_uri.path,
+                    params=parsed_uri.params,
+                    query=parsed_uri.query,
+                    fragment=parsed_uri.fragment,
+                )
+
+                res = yield self._route_matrix_uri(new_uri, lookup_well_known=False)
+                defer.returnValue(res)
+
+        # try a SRV lookup
+        service_name = b"_matrix._tcp.%s" % (parsed_uri.host,)
+        server_list = yield self._srv_resolver.resolve_service(service_name)
+
+        if not server_list:
+            target_host = parsed_uri.host
+            port = 8448
+            logger.debug(
+                "No SRV record for %s, using %s:%i",
+                parsed_uri.host.decode("ascii"), target_host.decode("ascii"), port,
+            )
+        else:
+            target_host, port = pick_server_from_list(server_list)
+            logger.debug(
+                "Picked %s:%i from SRV records for %s",
+                target_host.decode("ascii"), port, parsed_uri.host.decode("ascii"),
+            )
+
+        defer.returnValue(_RoutingResult(
+            host_header=parsed_uri.netloc,
+            tls_server_name=parsed_uri.host,
+            target_host=target_host,
+            target_port=port,
+        ))
+
+    @defer.inlineCallbacks
+    def _get_well_known(self, server_name):
+        """Attempt to fetch and parse a .well-known file for the given server
+
+        Args:
+            server_name (bytes): name of the server, from the requested url
+
+        Returns:
+            Deferred[bytes|None]: either the new server name, from the .well-known, or
+                None if there was no .well-known file.
+        """
+        try:
+            result = self._well_known_cache[server_name]
+        except KeyError:
+            # TODO: should we linearise so that we don't end up doing two .well-known
+            # requests for the same server in parallel?
+            with Measure(self._clock, "get_well_known"):
+                result, cache_period = yield self._do_get_well_known(server_name)
+
+            if cache_period > 0:
+                self._well_known_cache.set(server_name, result, cache_period)
+
+        defer.returnValue(result)
+
+    @defer.inlineCallbacks
+    def _do_get_well_known(self, server_name):
+        """Actually fetch and parse a .well-known, without checking the cache
+
+        Args:
+            server_name (bytes): name of the server, from the requested url
+
+        Returns:
+            Deferred[Tuple[bytes|None|object],int]:
+                result, cache period, where result is one of:
+                 - the new server name from the .well-known (as a `bytes`)
+                 - None if there was no .well-known file.
+                 - INVALID_WELL_KNOWN if the .well-known was invalid
+        """
+        uri = b"https://%s/.well-known/matrix/server" % (server_name, )
+        uri_str = uri.decode("ascii")
+        logger.info("Fetching %s", uri_str)
+        try:
+            response = yield make_deferred_yieldable(
+                self._well_known_agent.request(b"GET", uri),
+            )
+            body = yield make_deferred_yieldable(readBody(response))
+            if response.code != 200:
+                raise Exception("Non-200 response %s" % (response.code, ))
+
+            parsed_body = json.loads(body.decode('utf-8'))
+            logger.info("Response from .well-known: %s", parsed_body)
+            if not isinstance(parsed_body, dict):
+                raise Exception("not a dict")
+            if "m.server" not in parsed_body:
+                raise Exception("Missing key 'm.server'")
+        except Exception as e:
+            logger.info("Error fetching %s: %s", uri_str, e)
+
+            # add some randomness to the TTL to avoid a stampeding herd every hour
+            # after startup
+            cache_period = WELL_KNOWN_INVALID_CACHE_PERIOD
+            cache_period += random.uniform(0, WELL_KNOWN_DEFAULT_CACHE_PERIOD_JITTER)
+            defer.returnValue((None, cache_period))
+
+        result = parsed_body["m.server"].encode("ascii")
+
+        cache_period = _cache_period_from_headers(
+            response.headers,
+            time_now=self._reactor.seconds,
+        )
+        if cache_period is None:
+            cache_period = WELL_KNOWN_DEFAULT_CACHE_PERIOD
+            # add some randomness to the TTL to avoid a stampeding herd every 24 hours
+            # after startup
+            cache_period += random.uniform(0, WELL_KNOWN_DEFAULT_CACHE_PERIOD_JITTER)
+        else:
+            cache_period = min(cache_period, WELL_KNOWN_MAX_CACHE_PERIOD)
+
+        defer.returnValue((result, cache_period))
+
+
+@implementer(IStreamClientEndpoint)
+class LoggingHostnameEndpoint(object):
+    """A wrapper for HostnameEndpint which logs when it connects"""
+    def __init__(self, reactor, host, port, *args, **kwargs):
+        self.host = host
+        self.port = port
+        self.ep = HostnameEndpoint(reactor, host, port, *args, **kwargs)
+
+    def connect(self, protocol_factory):
+        logger.info("Connecting to %s:%i", self.host.decode("ascii"), self.port)
+        return self.ep.connect(protocol_factory)
+
+
+def _cache_period_from_headers(headers, time_now=time.time):
+    cache_controls = _parse_cache_control(headers)
+
+    if b'no-store' in cache_controls:
+        return 0
+
+    if b'max-age' in cache_controls:
+        try:
+            max_age = int(cache_controls[b'max-age'])
+            return max_age
+        except ValueError:
+            pass
+
+    expires = headers.getRawHeaders(b'expires')
+    if expires is not None:
+        try:
+            expires_date = stringToDatetime(expires[-1])
+            return expires_date - time_now()
+        except ValueError:
+            # RFC7234 says 'A cache recipient MUST interpret invalid date formats,
+            # especially the value "0", as representing a time in the past (i.e.,
+            # "already expired").
+            return 0
+
+    return None
+
+
+def _parse_cache_control(headers):
+    cache_controls = {}
+    for hdr in headers.getRawHeaders(b'cache-control', []):
+        for directive in hdr.split(b','):
+            splits = [x.strip() for x in directive.split(b'=', 1)]
+            k = splits[0].lower()
+            v = splits[1] if len(splits) > 1 else None
+            cache_controls[k] = v
+    return cache_controls
+
+
+@attr.s
+class _RoutingResult(object):
+    """The result returned by `_route_matrix_uri`.
+
+    Contains the parameters needed to direct a federation connection to a particular
+    server.
+
+    Where a SRV record points to several servers, this object contains a single server
+    chosen from the list.
+    """
+
+    host_header = attr.ib()
+    """
+    The value we should assign to the Host header (host:port from the matrix
+    URI, or .well-known).
+
+    :type: bytes
+    """
+
+    tls_server_name = attr.ib()
+    """
+    The server name we should set in the SNI (typically host, without port, from the
+    matrix URI or .well-known)
+
+    :type: bytes
+    """
+
+    target_host = attr.ib()
+    """
+    The hostname (or IP literal) we should route the TCP connection to (the target of the
+    SRV record, or the hostname from the URL/.well-known)
+
+    :type: bytes
+    """
+
+    target_port = attr.ib()
+    """
+    The port we should route the TCP connection to (the target of the SRV record, or
+    the port from the URL/.well-known, or 8448)
+
+    :type: int
+    """
diff --git a/synapse/http/federation/srv_resolver.py b/synapse/http/federation/srv_resolver.py
new file mode 100644
index 00000000..71830c54
--- /dev/null
+++ b/synapse/http/federation/srv_resolver.py
@@ -0,0 +1,169 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2019 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+import random
+import time
+
+import attr
+
+from twisted.internet import defer
+from twisted.internet.error import ConnectError
+from twisted.names import client, dns
+from twisted.names.error import DNSNameError, DomainError
+
+from synapse.util.logcontext import make_deferred_yieldable
+
+logger = logging.getLogger(__name__)
+
+SERVER_CACHE = {}
+
+
+@attr.s
+class Server(object):
+    """
+    Our record of an individual server which can be tried to reach a destination.
+
+    Attributes:
+        host (bytes): target hostname
+        port (int):
+        priority (int):
+        weight (int):
+        expires (int): when the cache should expire this record - in *seconds* since
+            the epoch
+    """
+    host = attr.ib()
+    port = attr.ib()
+    priority = attr.ib(default=0)
+    weight = attr.ib(default=0)
+    expires = attr.ib(default=0)
+
+
+def pick_server_from_list(server_list):
+    """Randomly choose a server from the server list
+
+    Args:
+        server_list (list[Server]): list of candidate servers
+
+    Returns:
+        Tuple[bytes, int]: (host, port) pair for the chosen server
+    """
+    if not server_list:
+        raise RuntimeError("pick_server_from_list called with empty list")
+
+    # TODO: currently we only use the lowest-priority servers. We should maintain a
+    # cache of servers known to be "down" and filter them out
+
+    min_priority = min(s.priority for s in server_list)
+    eligible_servers = list(s for s in server_list if s.priority == min_priority)
+    total_weight = sum(s.weight for s in eligible_servers)
+    target_weight = random.randint(0, total_weight)
+
+    for s in eligible_servers:
+        target_weight -= s.weight
+
+        if target_weight <= 0:
+            return s.host, s.port
+
+    # this should be impossible.
+    raise RuntimeError(
+        "pick_server_from_list got to end of eligible server list.",
+    )
+
+
+class SrvResolver(object):
+    """Interface to the dns client to do SRV lookups, with result caching.
+
+    The default resolver in twisted.names doesn't do any caching (it has a CacheResolver,
+    but the cache never gets populated), so we add our own caching layer here.
+
+    Args:
+        dns_client (twisted.internet.interfaces.IResolver): twisted resolver impl
+        cache (dict): cache object
+        get_time (callable): clock implementation. Should return seconds since the epoch
+    """
+    def __init__(self, dns_client=client, cache=SERVER_CACHE, get_time=time.time):
+        self._dns_client = dns_client
+        self._cache = cache
+        self._get_time = get_time
+
+    @defer.inlineCallbacks
+    def resolve_service(self, service_name):
+        """Look up a SRV record
+
+        Args:
+            service_name (bytes): record to look up
+
+        Returns:
+            Deferred[list[Server]]:
+                a list of the SRV records, or an empty list if none found
+        """
+        now = int(self._get_time())
+
+        if not isinstance(service_name, bytes):
+            raise TypeError("%r is not a byte string" % (service_name,))
+
+        cache_entry = self._cache.get(service_name, None)
+        if cache_entry:
+            if all(s.expires > now for s in cache_entry):
+                servers = list(cache_entry)
+                defer.returnValue(servers)
+
+        try:
+            answers, _, _ = yield make_deferred_yieldable(
+                self._dns_client.lookupService(service_name),
+            )
+        except DNSNameError:
+            # TODO: cache this. We can get the SOA out of the exception, and use
+            # the negative-TTL value.
+            defer.returnValue([])
+        except DomainError as e:
+            # We failed to resolve the name (other than a NameError)
+            # Try something in the cache, else rereaise
+            cache_entry = self._cache.get(service_name, None)
+            if cache_entry:
+                logger.warn(
+                    "Failed to resolve %r, falling back to cache. %r",
+                    service_name, e
+                )
+                defer.returnValue(list(cache_entry))
+            else:
+                raise e
+
+        if (len(answers) == 1
+                and answers[0].type == dns.SRV
+                and answers[0].payload
+                and answers[0].payload.target == dns.Name(b'.')):
+            raise ConnectError("Service %s unavailable" % service_name)
+
+        servers = []
+
+        for answer in answers:
+            if answer.type != dns.SRV or not answer.payload:
+                continue
+
+            payload = answer.payload
+
+            servers.append(Server(
+                host=payload.target.name,
+                port=payload.port,
+                priority=payload.priority,
+                weight=payload.weight,
+                expires=now + answer.ttl,
+            ))
+
+        self._cache[service_name] = list(servers)
+        defer.returnValue(servers)
diff --git a/synapse/http/matrixfederationclient.py b/synapse/http/matrixfederationclient.py
index be4076fc..bb2e64ed 100644
--- a/synapse/http/matrixfederationclient.py
+++ b/synapse/http/matrixfederationclient.py
@@ -32,7 +32,7 @@ from twisted.internet import defer, protocol
 from twisted.internet.error import DNSLookupError
 from twisted.internet.task import _EPSILON, Cooperator
 from twisted.web._newclient import ResponseDone
-from twisted.web.client import Agent, FileBodyProducer, HTTPConnectionPool
+from twisted.web.client import FileBodyProducer
 from twisted.web.http_headers import Headers
 
 import synapse.metrics
@@ -44,7 +44,7 @@ from synapse.api.errors import (
     RequestSendFailed,
     SynapseError,
 )
-from synapse.http.endpoint import matrix_federation_endpoint
+from synapse.http.federation.matrix_federation_agent import MatrixFederationAgent
 from synapse.util.async_helpers import timeout_deferred
 from synapse.util.logcontext import make_deferred_yieldable
 from synapse.util.metrics import Measure
@@ -66,20 +66,6 @@ else:
     MAXINT = sys.maxint
 
 
-class MatrixFederationEndpointFactory(object):
-    def __init__(self, hs):
-        self.reactor = hs.get_reactor()
-        self.tls_client_options_factory = hs.tls_client_options_factory
-
-    def endpointForURI(self, uri):
-        destination = uri.netloc.decode('ascii')
-
-        return matrix_federation_endpoint(
-            self.reactor, destination, timeout=10,
-            tls_client_options_factory=self.tls_client_options_factory
-        )
-
-
 _next_id = 1
 
 
@@ -187,12 +173,10 @@ class MatrixFederationHttpClient(object):
         self.signing_key = hs.config.signing_key[0]
         self.server_name = hs.hostname
         reactor = hs.get_reactor()
-        pool = HTTPConnectionPool(reactor)
-        pool.retryAutomatically = False
-        pool.maxPersistentPerHost = 5
-        pool.cachedConnectionTimeout = 2 * 60
-        self.agent = Agent.usingEndpointFactory(
-            reactor, MatrixFederationEndpointFactory(hs), pool=pool
+
+        self.agent = MatrixFederationAgent(
+            hs.get_reactor(),
+            hs.tls_client_options_factory,
         )
         self.clock = hs.get_clock()
         self._store = hs.get_datastore()
@@ -229,19 +213,18 @@ class MatrixFederationHttpClient(object):
             backoff_on_404 (bool): Back off if we get a 404
 
         Returns:
-            Deferred: resolves with the http response object on success.
-
-            Fails with ``HttpResponseException``: if we get an HTTP response
-                code >= 300 (except 429).
-
-            Fails with ``NotRetryingDestination`` if we are not yet ready
-                to retry this server.
-
-            Fails with ``FederationDeniedError`` if this destination
-                is not on our federation whitelist
-
-            Fails with ``RequestSendFailed`` if there were problems connecting to
-                the remote, due to e.g. DNS failures, connection timeouts etc.
+            Deferred[twisted.web.client.Response]: resolves with the HTTP
+            response object on success.
+
+        Raises:
+            HttpResponseException: If we get an HTTP response code >= 300
+                (except 429).
+            NotRetryingDestination: If we are not yet ready to retry this
+                server.
+            FederationDeniedError: If this destination  is not on our
+                federation whitelist
+            RequestSendFailed: If there were problems connecting to the
+                remote, due to e.g. DNS failures, connection timeouts etc.
         """
         if timeout:
             _sec_timeout = timeout / 1000
@@ -272,7 +255,6 @@ class MatrixFederationHttpClient(object):
 
         headers_dict = {
             b"User-Agent": [self.version_string_bytes],
-            b"Host": [destination_bytes],
         }
 
         with limiter:
@@ -299,9 +281,9 @@ class MatrixFederationHttpClient(object):
                     json = request.get_json()
                     if json:
                         headers_dict[b"Content-Type"] = [b"application/json"]
-                        self.sign_request(
+                        auth_headers = self.build_auth_headers(
                             destination_bytes, method_bytes, url_to_sign_bytes,
-                            headers_dict, json,
+                            json,
                         )
                         data = encode_canonical_json(json)
                         producer = FileBodyProducer(
@@ -310,40 +292,40 @@ class MatrixFederationHttpClient(object):
                         )
                     else:
                         producer = None
-                        self.sign_request(
+                        auth_headers = self.build_auth_headers(
                             destination_bytes, method_bytes, url_to_sign_bytes,
-                            headers_dict,
                         )
 
+                    headers_dict[b"Authorization"] = auth_headers
+
                     logger.info(
-                        "{%s} [%s] Sending request: %s %s",
+                        "{%s} [%s] Sending request: %s %s; timeout %fs",
                         request.txn_id, request.destination, request.method,
-                        url_str,
-                    )
-
-                    # we don't want all the fancy cookie and redirect handling that
-                    # treq.request gives: just use the raw Agent.
-                    request_deferred = self.agent.request(
-                        method_bytes,
-                        url_bytes,
-                        headers=Headers(headers_dict),
-                        bodyProducer=producer,
-                    )
-
-                    request_deferred = timeout_deferred(
-                        request_deferred,
-                        timeout=_sec_timeout,
-                        reactor=self.hs.get_reactor(),
+                        url_str, _sec_timeout,
                     )
 
                     try:
                         with Measure(self.clock, "outbound_request"):
-                            response = yield make_deferred_yieldable(
+                            # we don't want all the fancy cookie and redirect handling
+                            # that treq.request gives: just use the raw Agent.
+                            request_deferred = self.agent.request(
+                                method_bytes,
+                                url_bytes,
+                                headers=Headers(headers_dict),
+                                bodyProducer=producer,
+                            )
+
+                            request_deferred = timeout_deferred(
                                 request_deferred,
+                                timeout=_sec_timeout,
+                                reactor=self.hs.get_reactor(),
                             )
+
+                            response = yield request_deferred
                     except DNSLookupError as e:
                         raise_from(RequestSendFailed(e, can_retry=retry_on_dns_fail), e)
                     except Exception as e:
+                        logger.info("Failed to send request: %s", e)
                         raise_from(RequestSendFailed(e, can_retry=True), e)
 
                     logger.info(
@@ -441,24 +423,23 @@ class MatrixFederationHttpClient(object):
 
             defer.returnValue(response)
 
-    def sign_request(self, destination, method, url_bytes, headers_dict,
-                     content=None, destination_is=None):
+    def build_auth_headers(
+        self, destination, method, url_bytes, content=None, destination_is=None,
+    ):
         """
-        Signs a request by adding an Authorization header to headers_dict
+        Builds the Authorization headers for a federation request
         Args:
             destination (bytes|None): The desination home server of the request.
                 May be None if the destination is an identity server, in which case
                 destination_is must be non-None.
             method (bytes): The HTTP method of the request
             url_bytes (bytes): The URI path of the request
-            headers_dict (dict[bytes, list[bytes]]): Dictionary of request headers to
-                append to
             content (object): The body of the request
             destination_is (bytes): As 'destination', but if the destination is an
                 identity server
 
         Returns:
-            None
+            list[bytes]: a list of headers to be added as "Authorization:" headers
         """
         request = {
             "method": method,
@@ -485,8 +466,7 @@ class MatrixFederationHttpClient(object):
                     self.server_name, key, sig,
                 )).encode('ascii')
             )
-
-        headers_dict[b"Authorization"] = auth_headers
+        return auth_headers
 
     @defer.inlineCallbacks
     def put_json(self, destination, path, args={}, data={},
@@ -516,17 +496,18 @@ class MatrixFederationHttpClient(object):
                 requests)
 
         Returns:
-            Deferred: Succeeds when we get a 2xx HTTP response. The result
-            will be the decoded JSON body.
-
-            Fails with ``HttpResponseException`` if we get an HTTP response
-            code >= 300.
-
-            Fails with ``NotRetryingDestination`` if we are not yet ready
-            to retry this server.
-
-            Fails with ``FederationDeniedError`` if this destination
-            is not on our federation whitelist
+            Deferred[dict|list]: Succeeds when we get a 2xx HTTP response. The
+            result will be the decoded JSON body.
+
+        Raises:
+            HttpResponseException: If we get an HTTP response code >= 300
+                (except 429).
+            NotRetryingDestination: If we are not yet ready to retry this
+                server.
+            FederationDeniedError: If this destination  is not on our
+                federation whitelist
+            RequestSendFailed: If there were problems connecting to the
+                remote, due to e.g. DNS failures, connection timeouts etc.
         """
 
         request = MatrixFederationRequest(
@@ -570,17 +551,18 @@ class MatrixFederationHttpClient(object):
                 try the request anyway.
             args (dict): query params
         Returns:
-            Deferred: Succeeds when we get a 2xx HTTP response. The result
-            will be the decoded JSON body.
-
-            Fails with ``HttpResponseException`` if we get an HTTP response
-            code >= 300.
-
-            Fails with ``NotRetryingDestination`` if we are not yet ready
-            to retry this server.
-
-            Fails with ``FederationDeniedError`` if this destination
-            is not on our federation whitelist
+            Deferred[dict|list]: Succeeds when we get a 2xx HTTP response. The
+            result will be the decoded JSON body.
+
+        Raises:
+            HttpResponseException: If we get an HTTP response code >= 300
+                (except 429).
+            NotRetryingDestination: If we are not yet ready to retry this
+                server.
+            FederationDeniedError: If this destination  is not on our
+                federation whitelist
+            RequestSendFailed: If there were problems connecting to the
+                remote, due to e.g. DNS failures, connection timeouts etc.
         """
 
         request = MatrixFederationRequest(
@@ -625,17 +607,18 @@ class MatrixFederationHttpClient(object):
             ignore_backoff (bool): true to ignore the historical backoff data
                 and try the request anyway.
         Returns:
-            Deferred: Succeeds when we get a 2xx HTTP response. The result
-            will be the decoded JSON body.
-
-            Fails with ``HttpResponseException`` if we get an HTTP response
-            code >= 300.
-
-            Fails with ``NotRetryingDestination`` if we are not yet ready
-            to retry this server.
-
-            Fails with ``FederationDeniedError`` if this destination
-            is not on our federation whitelist
+            Deferred[dict|list]: Succeeds when we get a 2xx HTTP response. The
+            result will be the decoded JSON body.
+
+        Raises:
+            HttpResponseException: If we get an HTTP response code >= 300
+                (except 429).
+            NotRetryingDestination: If we are not yet ready to retry this
+                server.
+            FederationDeniedError: If this destination  is not on our
+                federation whitelist
+            RequestSendFailed: If there were problems connecting to the
+                remote, due to e.g. DNS failures, connection timeouts etc.
         """
         logger.debug("get_json args: %s", args)
 
@@ -676,17 +659,18 @@ class MatrixFederationHttpClient(object):
             ignore_backoff (bool): true to ignore the historical backoff data and
                 try the request anyway.
         Returns:
-            Deferred: Succeeds when we get a 2xx HTTP response. The result
-            will be the decoded JSON body.
-
-            Fails with ``HttpResponseException`` if we get an HTTP response
-            code >= 300.
-
-            Fails with ``NotRetryingDestination`` if we are not yet ready
-            to retry this server.
-
-            Fails with ``FederationDeniedError`` if this destination
-            is not on our federation whitelist
+            Deferred[dict|list]: Succeeds when we get a 2xx HTTP response. The
+            result will be the decoded JSON body.
+
+        Raises:
+            HttpResponseException: If we get an HTTP response code >= 300
+                (except 429).
+            NotRetryingDestination: If we are not yet ready to retry this
+                server.
+            FederationDeniedError: If this destination  is not on our
+                federation whitelist
+            RequestSendFailed: If there were problems connecting to the
+                remote, due to e.g. DNS failures, connection timeouts etc.
         """
         request = MatrixFederationRequest(
             method="DELETE",
@@ -719,18 +703,20 @@ class MatrixFederationHttpClient(object):
             args (dict): Optional dictionary used to create the query string.
             ignore_backoff (bool): true to ignore the historical backoff data
                 and try the request anyway.
-        Returns:
-            Deferred: resolves with an (int,dict) tuple of the file length and
-            a dict of the response headers.
-
-            Fails with ``HttpResponseException`` if we get an HTTP response code
-            >= 300
 
-            Fails with ``NotRetryingDestination`` if we are not yet ready
-            to retry this server.
-
-            Fails with ``FederationDeniedError`` if this destination
-            is not on our federation whitelist
+        Returns:
+            Deferred[tuple[int, dict]]: Resolves with an (int,dict) tuple of
+            the file length and a dict of the response headers.
+
+        Raises:
+            HttpResponseException: If we get an HTTP response code >= 300
+                (except 429).
+            NotRetryingDestination: If we are not yet ready to retry this
+                server.
+            FederationDeniedError: If this destination  is not on our
+                federation whitelist
+            RequestSendFailed: If there were problems connecting to the
+                remote, due to e.g. DNS failures, connection timeouts etc.
         """
         request = MatrixFederationRequest(
             method="GET",
diff --git a/synapse/push/clientformat.py b/synapse/push/clientformat.py
index ecbf364a..8bd96b11 100644
--- a/synapse/push/clientformat.py
+++ b/synapse/push/clientformat.py
@@ -84,7 +84,7 @@ def _rule_to_template(rule):
         templaterule["pattern"] = thecond["pattern"]
 
     if unscoped_rule_id:
-            templaterule['rule_id'] = unscoped_rule_id
+        templaterule['rule_id'] = unscoped_rule_id
     if 'default' in rule:
         templaterule['default'] = rule['default']
     return templaterule
diff --git a/synapse/python_dependencies.py b/synapse/python_dependencies.py
index 69c5f9fe..756721e3 100644
--- a/synapse/python_dependencies.py
+++ b/synapse/python_dependencies.py
@@ -40,7 +40,11 @@ REQUIREMENTS = [
     "signedjson>=1.0.0",
     "pynacl>=1.2.1",
     "service_identity>=16.0.0",
-    "Twisted>=17.1.0",
+
+    # our logcontext handling relies on the ability to cancel inlineCallbacks
+    # (https://twistedmatrix.com/trac/ticket/4632) which landed in Twisted 18.7.
+    "Twisted>=18.7.0",
+
     "treq>=15.1",
     # Twisted has required pyopenssl 16.0 since about Twisted 16.6.
     "pyopenssl>=16.0.0",
@@ -52,15 +56,18 @@ REQUIREMENTS = [
     "pillow>=3.1.2",
     "sortedcontainers>=1.4.4",
     "psutil>=2.0.0",
-    "pymacaroons-pynacl>=0.9.3",
-    "msgpack-python>=0.4.2",
+    "pymacaroons>=0.13.0",
+    "msgpack>=0.5.0",
     "phonenumbers>=8.2.0",
     "six>=1.10",
     # prometheus_client 0.4.0 changed the format of counter metrics
     # (cf https://github.com/matrix-org/synapse/issues/4001)
     "prometheus_client>=0.0.18,<0.4.0",
+
     # we use attr.s(slots), which arrived in 16.0.0
-    "attrs>=16.0.0",
+    # Twisted 18.7.0 requires attrs>=17.4.0
+    "attrs>=17.4.0",
+
     "netaddr>=0.7.18",
 ]
 
@@ -72,6 +79,10 @@ CONDITIONAL_REQUIREMENTS = {
     # ConsentResource uses select_autoescape, which arrived in jinja 2.9
     "resources.consent": ["Jinja2>=2.9"],
 
+    # ACME support is required to provision TLS certificates from authorities
+    # that use the protocol, such as Let's Encrypt.
+    "acme": ["txacme>=0.9.2"],
+
     "saml2": ["pysaml2>=4.5.0"],
     "url_preview": ["lxml>=3.5.0"],
     "test": ["mock>=2.0"],
diff --git a/synapse/replication/http/_base.py b/synapse/replication/http/_base.py
index 5e5376cf..e81456ab 100644
--- a/synapse/replication/http/_base.py
+++ b/synapse/replication/http/_base.py
@@ -127,7 +127,10 @@ class ReplicationEndpoint(object):
         def send_request(**kwargs):
             data = yield cls._serialize_payload(**kwargs)
 
-            url_args = [urllib.parse.quote(kwargs[name]) for name in cls.PATH_ARGS]
+            url_args = [
+                urllib.parse.quote(kwargs[name], safe='')
+                for name in cls.PATH_ARGS
+            ]
 
             if cls.CACHE:
                 txn_id = random_string(10)
diff --git a/synapse/replication/http/federation.py b/synapse/replication/http/federation.py
index 64a79da1..0f0a07c4 100644
--- a/synapse/replication/http/federation.py
+++ b/synapse/replication/http/federation.py
@@ -17,7 +17,7 @@ import logging
 
 from twisted.internet import defer
 
-from synapse.events import FrozenEvent
+from synapse.events import event_type_from_format_version
 from synapse.events.snapshot import EventContext
 from synapse.http.servlet import parse_json_object_from_request
 from synapse.replication.http._base import ReplicationEndpoint
@@ -70,6 +70,7 @@ class ReplicationFederationSendEventsRestServlet(ReplicationEndpoint):
 
             event_payloads.append({
                 "event": event.get_pdu_json(),
+                "event_format_version": event.format_version,
                 "internal_metadata": event.internal_metadata.get_dict(),
                 "rejected_reason": event.rejected_reason,
                 "context": serialized_context,
@@ -94,9 +95,12 @@ class ReplicationFederationSendEventsRestServlet(ReplicationEndpoint):
             event_and_contexts = []
             for event_payload in event_payloads:
                 event_dict = event_payload["event"]
+                format_ver = event_payload["event_format_version"]
                 internal_metadata = event_payload["internal_metadata"]
                 rejected_reason = event_payload["rejected_reason"]
-                event = FrozenEvent(event_dict, internal_metadata, rejected_reason)
+
+                EventType = event_type_from_format_version(format_ver)
+                event = EventType(event_dict, internal_metadata, rejected_reason)
 
                 context = yield EventContext.deserialize(
                     self.store, event_payload["context"],
diff --git a/synapse/replication/http/send_event.py b/synapse/replication/http/send_event.py
index 5b52c916..3635015e 100644
--- a/synapse/replication/http/send_event.py
+++ b/synapse/replication/http/send_event.py
@@ -17,7 +17,7 @@ import logging
 
 from twisted.internet import defer
 
-from synapse.events import FrozenEvent
+from synapse.events import event_type_from_format_version
 from synapse.events.snapshot import EventContext
 from synapse.http.servlet import parse_json_object_from_request
 from synapse.replication.http._base import ReplicationEndpoint
@@ -74,6 +74,7 @@ class ReplicationSendEventRestServlet(ReplicationEndpoint):
 
         payload = {
             "event": event.get_pdu_json(),
+            "event_format_version": event.format_version,
             "internal_metadata": event.internal_metadata.get_dict(),
             "rejected_reason": event.rejected_reason,
             "context": serialized_context,
@@ -90,9 +91,12 @@ class ReplicationSendEventRestServlet(ReplicationEndpoint):
             content = parse_json_object_from_request(request)
 
             event_dict = content["event"]
+            format_ver = content["event_format_version"]
             internal_metadata = content["internal_metadata"]
             rejected_reason = content["rejected_reason"]
-            event = FrozenEvent(event_dict, internal_metadata, rejected_reason)
+
+            EventType = event_type_from_format_version(format_ver)
+            event = EventType(event_dict, internal_metadata, rejected_reason)
 
             requester = Requester.deserialize(self.store, content["requester"])
             context = yield EventContext.deserialize(self.store, content["context"])
diff --git a/synapse/rest/__init__.py b/synapse/rest/__init__.py
index 66585c99..91f5247d 100644
--- a/synapse/rest/__init__.py
+++ b/synapse/rest/__init__.py
@@ -34,6 +34,7 @@ from synapse.rest.client.v2_alpha import (
     account,
     account_data,
     auth,
+    capabilities,
     devices,
     filter,
     groups,
@@ -107,3 +108,4 @@ class ClientRestResource(JsonResource):
         user_directory.register_servlets(hs, client_resource)
         groups.register_servlets(hs, client_resource)
         room_upgrade_rest_servlet.register_servlets(hs, client_resource)
+        capabilities.register_servlets(hs, client_resource)
diff --git a/synapse/rest/client/v1/room.py b/synapse/rest/client/v1/room.py
index fcfe7857..48da4d55 100644
--- a/synapse/rest/client/v1/room.py
+++ b/synapse/rest/client/v1/room.py
@@ -89,7 +89,7 @@ class RoomStateEventRestServlet(ClientV1RestServlet):
     def __init__(self, hs):
         super(RoomStateEventRestServlet, self).__init__(hs)
         self.handlers = hs.get_handlers()
-        self.event_creation_hander = hs.get_event_creation_handler()
+        self.event_creation_handler = hs.get_event_creation_handler()
         self.room_member_handler = hs.get_room_member_handler()
         self.message_handler = hs.get_message_handler()
 
@@ -172,7 +172,7 @@ class RoomStateEventRestServlet(ClientV1RestServlet):
                 content=content,
             )
         else:
-            event = yield self.event_creation_hander.create_and_send_nonmember_event(
+            event = yield self.event_creation_handler.create_and_send_nonmember_event(
                 requester,
                 event_dict,
                 txn_id=txn_id,
@@ -189,7 +189,7 @@ class RoomSendEventRestServlet(ClientV1RestServlet):
 
     def __init__(self, hs):
         super(RoomSendEventRestServlet, self).__init__(hs)
-        self.event_creation_hander = hs.get_event_creation_handler()
+        self.event_creation_handler = hs.get_event_creation_handler()
 
     def register(self, http_server):
         # /rooms/$roomid/send/$event_type[/$txn_id]
@@ -211,7 +211,7 @@ class RoomSendEventRestServlet(ClientV1RestServlet):
         if b'ts' in request.args and requester.app_service:
             event_dict['origin_server_ts'] = parse_integer(request, "ts", 0)
 
-        event = yield self.event_creation_hander.create_and_send_nonmember_event(
+        event = yield self.event_creation_handler.create_and_send_nonmember_event(
             requester,
             event_dict,
             txn_id=txn_id,
diff --git a/synapse/rest/client/v2_alpha/capabilities.py b/synapse/rest/client/v2_alpha/capabilities.py
new file mode 100644
index 00000000..373f9512
--- /dev/null
+++ b/synapse/rest/client/v2_alpha/capabilities.py
@@ -0,0 +1,66 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 New Vector
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import logging
+
+from twisted.internet import defer
+
+from synapse.api.constants import DEFAULT_ROOM_VERSION, RoomDisposition, RoomVersions
+from synapse.http.servlet import RestServlet
+
+from ._base import client_v2_patterns
+
+logger = logging.getLogger(__name__)
+
+
+class CapabilitiesRestServlet(RestServlet):
+    """End point to expose the capabilities of the server."""
+
+    PATTERNS = client_v2_patterns("/capabilities$")
+
+    def __init__(self, hs):
+        """
+        Args:
+            hs (synapse.server.HomeServer): server
+        """
+        super(CapabilitiesRestServlet, self).__init__()
+        self.hs = hs
+        self.auth = hs.get_auth()
+        self.store = hs.get_datastore()
+
+    @defer.inlineCallbacks
+    def on_GET(self, request):
+        requester = yield self.auth.get_user_by_req(request, allow_guest=True)
+        user = yield self.store.get_user_by_id(requester.user.to_string())
+        change_password = bool(user["password_hash"])
+
+        response = {
+            "capabilities": {
+                "m.room_versions": {
+                    "default": DEFAULT_ROOM_VERSION,
+                    "available": {
+                        RoomVersions.V1: RoomDisposition.STABLE,
+                        RoomVersions.V2: RoomDisposition.STABLE,
+                        RoomVersions.STATE_V2_TEST: RoomDisposition.UNSTABLE,
+                        RoomVersions.V3: RoomDisposition.STABLE,
+                    },
+                },
+                "m.change_password": {"enabled": change_password},
+            }
+        }
+        defer.returnValue((200, response))
+
+
+def register_servlets(hs, http_server):
+    CapabilitiesRestServlet(hs).register(http_server)
diff --git a/synapse/rest/client/v2_alpha/register.py b/synapse/rest/client/v2_alpha/register.py
index aec0c6b0..7f812b82 100644
--- a/synapse/rest/client/v2_alpha/register.py
+++ b/synapse/rest/client/v2_alpha/register.py
@@ -309,22 +309,16 @@ class RegisterRestServlet(RestServlet):
                 assigned_user_id=registered_user_id,
             )
 
-        # Only give msisdn flows if the x_show_msisdn flag is given:
-        # this is a hack to work around the fact that clients were shipped
-        # that use fallback registration if they see any flows that they don't
-        # recognise, which means we break registration for these clients if we
-        # advertise msisdn flows. Once usage of Riot iOS <=0.3.9 and Riot
-        # Android <=0.6.9 have fallen below an acceptable threshold, this
-        # parameter should go away and we should always advertise msisdn flows.
-        show_msisdn = False
-        if 'x_show_msisdn' in body and body['x_show_msisdn']:
-            show_msisdn = True
-
         # FIXME: need a better error than "no auth flow found" for scenarios
         # where we required 3PID for registration but the user didn't give one
         require_email = 'email' in self.hs.config.registrations_require_3pid
         require_msisdn = 'msisdn' in self.hs.config.registrations_require_3pid
 
+        show_msisdn = True
+        if self.hs.config.disable_msisdn_registration:
+            show_msisdn = False
+            require_msisdn = False
+
         flows = []
         if self.hs.config.enable_registration_captcha:
             # only support 3PIDless registration if no 3PIDs are required
@@ -422,8 +416,11 @@ class RegisterRestServlet(RestServlet):
             )
             # Necessary due to auth checks prior to the threepid being
             # written to the db
-            if is_threepid_reserved(self.hs.config, threepid):
-                yield self.store.upsert_monthly_active_user(registered_user_id)
+            if threepid:
+                if is_threepid_reserved(
+                    self.hs.config.mau_limits_reserved_threepids, threepid
+                ):
+                    yield self.store.upsert_monthly_active_user(registered_user_id)
 
             # remember that we've now registered that user account, and with
             #  what user ID (since the user may not have specified)
diff --git a/synapse/rest/consent/consent_resource.py b/synapse/rest/consent/consent_resource.py
index 80611cfe..008d4eda 100644
--- a/synapse/rest/consent/consent_resource.py
+++ b/synapse/rest/consent/consent_resource.py
@@ -101,16 +101,7 @@ class ConsentResource(Resource):
                 "missing in config file.",
             )
 
-        # daemonize changes the cwd to /, so make the path absolute now.
-        consent_template_directory = path.abspath(
-            hs.config.user_consent_template_dir,
-        )
-        if not path.isdir(consent_template_directory):
-            raise ConfigError(
-                "Could not find template directory '%s'" % (
-                    consent_template_directory,
-                ),
-            )
+        consent_template_directory = hs.config.user_consent_template_dir
 
         loader = jinja2.FileSystemLoader(consent_template_directory)
         self._jinja_env = jinja2.Environment(
diff --git a/synapse/server.py b/synapse/server.py
index 9985687b..6c521016 100644
--- a/synapse/server.py
+++ b/synapse/server.py
@@ -46,6 +46,7 @@ from synapse.federation.transport.client import TransportLayerClient
 from synapse.groups.attestations import GroupAttestationSigning, GroupAttestionRenewer
 from synapse.groups.groups_server import GroupsServerHandler
 from synapse.handlers import Handlers
+from synapse.handlers.acme import AcmeHandler
 from synapse.handlers.appservice import ApplicationServicesHandler
 from synapse.handlers.auth import AuthHandler, MacaroonGenerator
 from synapse.handlers.deactivate_account import DeactivateAccountHandler
@@ -129,6 +130,7 @@ class HomeServer(object):
         'sync_handler',
         'typing_handler',
         'room_list_handler',
+        'acme_handler',
         'auth_handler',
         'device_handler',
         'e2e_keys_handler',
@@ -310,6 +312,9 @@ class HomeServer(object):
     def build_e2e_room_keys_handler(self):
         return E2eRoomKeysHandler(self)
 
+    def build_acme_handler(self):
+        return AcmeHandler(self)
+
     def build_application_service_api(self):
         return ApplicationServiceApi(self)
 
@@ -350,10 +355,7 @@ class HomeServer(object):
         return Keyring(self)
 
     def build_event_builder_factory(self):
-        return EventBuilderFactory(
-            clock=self.get_clock(),
-            hostname=self.hostname,
-        )
+        return EventBuilderFactory(self)
 
     def build_filtering(self):
         return Filtering(self)
diff --git a/synapse/state/__init__.py b/synapse/state/__init__.py
index e9ecb002..68058f61 100644
--- a/synapse/state/__init__.py
+++ b/synapse/state/__init__.py
@@ -608,10 +608,10 @@ def resolve_events_with_store(room_version, state_sets, event_map, state_res_sto
             state_sets, event_map, state_res_store.get_events,
         )
     elif room_version in (
-        RoomVersions.VDH_TEST, RoomVersions.STATE_V2_TEST, RoomVersions.V2,
+        RoomVersions.STATE_V2_TEST, RoomVersions.V2, RoomVersions.V3,
     ):
         return v2.resolve_events_with_store(
-            state_sets, event_map, state_res_store,
+            room_version, state_sets, event_map, state_res_store,
         )
     else:
         # This should only happen if we added a version but forgot to add it to
diff --git a/synapse/state/v1.py b/synapse/state/v1.py
index 19e091ce..6d3afcae 100644
--- a/synapse/state/v1.py
+++ b/synapse/state/v1.py
@@ -21,7 +21,7 @@ from six import iteritems, iterkeys, itervalues
 from twisted.internet import defer
 
 from synapse import event_auth
-from synapse.api.constants import EventTypes
+from synapse.api.constants import EventTypes, RoomVersions
 from synapse.api.errors import AuthError
 
 logger = logging.getLogger(__name__)
@@ -274,7 +274,11 @@ def _resolve_auth_events(events, auth_events):
         auth_events[(prev_event.type, prev_event.state_key)] = prev_event
         try:
             # The signatures have already been checked at this point
-            event_auth.check(event, auth_events, do_sig_check=False, do_size_check=False)
+            event_auth.check(
+                RoomVersions.V1, event, auth_events,
+                do_sig_check=False,
+                do_size_check=False,
+            )
             prev_event = event
         except AuthError:
             return prev_event
@@ -286,7 +290,11 @@ def _resolve_normal_events(events, auth_events):
     for event in _ordered_events(events):
         try:
             # The signatures have already been checked at this point
-            event_auth.check(event, auth_events, do_sig_check=False, do_size_check=False)
+            event_auth.check(
+                RoomVersions.V1, event, auth_events,
+                do_sig_check=False,
+                do_size_check=False,
+            )
             return event
         except AuthError:
             pass
diff --git a/synapse/state/v2.py b/synapse/state/v2.py
index 3573bb00..650995c9 100644
--- a/synapse/state/v2.py
+++ b/synapse/state/v2.py
@@ -29,10 +29,12 @@ logger = logging.getLogger(__name__)
 
 
 @defer.inlineCallbacks
-def resolve_events_with_store(state_sets, event_map, state_res_store):
+def resolve_events_with_store(room_version, state_sets, event_map, state_res_store):
     """Resolves the state using the v2 state resolution algorithm
 
     Args:
+        room_version (str): The room version
+
         state_sets(list): List of dicts of (type, state_key) -> event_id,
             which are the different state groups to resolve.
 
@@ -104,7 +106,7 @@ def resolve_events_with_store(state_sets, event_map, state_res_store):
 
     # Now sequentially auth each one
     resolved_state = yield _iterative_auth_checks(
-        sorted_power_events, unconflicted_state, event_map,
+        room_version, sorted_power_events, unconflicted_state, event_map,
         state_res_store,
     )
 
@@ -129,7 +131,7 @@ def resolve_events_with_store(state_sets, event_map, state_res_store):
     logger.debug("resolving remaining events")
 
     resolved_state = yield _iterative_auth_checks(
-        leftover_events, resolved_state, event_map,
+        room_version, leftover_events, resolved_state, event_map,
         state_res_store,
     )
 
@@ -350,11 +352,13 @@ def _reverse_topological_power_sort(event_ids, event_map, state_res_store, auth_
 
 
 @defer.inlineCallbacks
-def _iterative_auth_checks(event_ids, base_state, event_map, state_res_store):
+def _iterative_auth_checks(room_version, event_ids, base_state, event_map,
+                           state_res_store):
     """Sequentially apply auth checks to each event in given list, updating the
     state as it goes along.
 
     Args:
+        room_version (str)
         event_ids (list[str]): Ordered list of events to apply auth checks to
         base_state (dict[tuple[str, str], str]): The set of state to start with
         event_map (dict[str,FrozenEvent])
@@ -385,7 +389,7 @@ def _iterative_auth_checks(event_ids, base_state, event_map, state_res_store):
 
         try:
             event_auth.check(
-                event, auth_events,
+                room_version, event, auth_events,
                 do_sig_check=False,
                 do_size_check=False
             )
diff --git a/synapse/storage/__init__.py b/synapse/storage/__init__.py
index 24329879..42cd3c83 100644
--- a/synapse/storage/__init__.py
+++ b/synapse/storage/__init__.py
@@ -317,7 +317,7 @@ class DataStore(RoomMemberStore, RoomStore,
                               thirty_days_ago_in_secs))
 
             for row in txn:
-                if row[0] is 'unknown':
+                if row[0] == 'unknown':
                     pass
                 results[row[0]] = row[1]
 
diff --git a/synapse/storage/_base.py b/synapse/storage/_base.py
index 1d3069b1..4872ff55 100644
--- a/synapse/storage/_base.py
+++ b/synapse/storage/_base.py
@@ -26,7 +26,8 @@ from prometheus_client import Histogram
 from twisted.internet import defer
 
 from synapse.api.errors import StoreError
-from synapse.storage.engines import PostgresEngine
+from synapse.metrics.background_process_metrics import run_as_background_process
+from synapse.storage.engines import PostgresEngine, Sqlite3Engine
 from synapse.util.caches.descriptors import Cache
 from synapse.util.logcontext import LoggingContext, PreserveLoggingContext
 from synapse.util.stringutils import exception_to_unicode
@@ -192,6 +193,57 @@ class SQLBaseStore(object):
 
         self.database_engine = hs.database_engine
 
+        # A set of tables that are not safe to use native upserts in.
+        self._unsafe_to_upsert_tables = {"user_ips"}
+
+        # We add the user_directory_search table to the blacklist on SQLite
+        # because the existing search table does not have an index, making it
+        # unsafe to use native upserts.
+        if isinstance(self.database_engine, Sqlite3Engine):
+            self._unsafe_to_upsert_tables.add("user_directory_search")
+
+        if self.database_engine.can_native_upsert:
+            # Check ASAP (and then later, every 1s) to see if we have finished
+            # background updates of tables that aren't safe to update.
+            self._clock.call_later(
+                0.0,
+                run_as_background_process,
+                "upsert_safety_check",
+                self._check_safe_to_upsert
+            )
+
+    @defer.inlineCallbacks
+    def _check_safe_to_upsert(self):
+        """
+        Is it safe to use native UPSERT?
+
+        If there are background updates, we will need to wait, as they may be
+        the addition of indexes that set the UNIQUE constraint that we require.
+
+        If the background updates have not completed, wait 15 sec and check again.
+        """
+        updates = yield self._simple_select_list(
+            "background_updates",
+            keyvalues=None,
+            retcols=["update_name"],
+            desc="check_background_updates",
+        )
+        updates = [x["update_name"] for x in updates]
+
+        # The User IPs table in schema #53 was missing a unique index, which we
+        # run as a background update.
+        if "user_ips_device_unique_index" not in updates:
+            self._unsafe_to_upsert_tables.discard("user_ips")
+
+        # If there's any tables left to check, reschedule to run.
+        if updates:
+            self._clock.call_later(
+                15.0,
+                run_as_background_process,
+                "upsert_safety_check",
+                self._check_safe_to_upsert
+            )
+
     def start_profiling(self):
         self._previous_loop_ts = self._clock.time_msec()
 
@@ -494,8 +546,15 @@ class SQLBaseStore(object):
         txn.executemany(sql, vals)
 
     @defer.inlineCallbacks
-    def _simple_upsert(self, table, keyvalues, values,
-                       insertion_values={}, desc="_simple_upsert", lock=True):
+    def _simple_upsert(
+        self,
+        table,
+        keyvalues,
+        values,
+        insertion_values={},
+        desc="_simple_upsert",
+        lock=True
+    ):
         """
 
         `lock` should generally be set to True (the default), but can be set
@@ -516,16 +575,21 @@ class SQLBaseStore(object):
                 inserting
             lock (bool): True to lock the table when doing the upsert.
         Returns:
-            Deferred(bool): True if a new entry was created, False if an
-                existing one was updated.
+            Deferred(None or bool): Native upserts always return None. Emulated
+            upserts return True if a new entry was created, False if an existing
+            one was updated.
         """
         attempts = 0
         while True:
             try:
                 result = yield self.runInteraction(
                     desc,
-                    self._simple_upsert_txn, table, keyvalues, values, insertion_values,
-                    lock=lock
+                    self._simple_upsert_txn,
+                    table,
+                    keyvalues,
+                    values,
+                    insertion_values,
+                    lock=lock,
                 )
                 defer.returnValue(result)
             except self.database_engine.module.IntegrityError as e:
@@ -537,21 +601,88 @@ class SQLBaseStore(object):
 
                 # presumably we raced with another transaction: let's retry.
                 logger.warn(
-                    "IntegrityError when upserting into %s; retrying: %s",
-                    table, e
+                    "%s when upserting into %s; retrying: %s", e.__name__, table, e
                 )
 
-    def _simple_upsert_txn(self, txn, table, keyvalues, values, insertion_values={},
-                           lock=True):
+    def _simple_upsert_txn(
+        self,
+        txn,
+        table,
+        keyvalues,
+        values,
+        insertion_values={},
+        lock=True,
+    ):
+        """
+        Pick the UPSERT method which works best on the platform. Either the
+        native one (Pg9.5+, recent SQLites), or fall back to an emulated method.
+
+        Args:
+            txn: The transaction to use.
+            table (str): The table to upsert into
+            keyvalues (dict): The unique key tables and their new values
+            values (dict): The nonunique columns and their new values
+            insertion_values (dict): additional key/values to use only when
+                inserting
+            lock (bool): True to lock the table when doing the upsert.
+        Returns:
+            None or bool: Native upserts always return None. Emulated
+            upserts return True if a new entry was created, False if an existing
+            one was updated.
+        """
+        if (
+            self.database_engine.can_native_upsert
+            and table not in self._unsafe_to_upsert_tables
+        ):
+            return self._simple_upsert_txn_native_upsert(
+                txn,
+                table,
+                keyvalues,
+                values,
+                insertion_values=insertion_values,
+            )
+        else:
+            return self._simple_upsert_txn_emulated(
+                txn,
+                table,
+                keyvalues,
+                values,
+                insertion_values=insertion_values,
+                lock=lock,
+            )
+
+    def _simple_upsert_txn_emulated(
+        self, txn, table, keyvalues, values, insertion_values={}, lock=True
+    ):
+        """
+        Args:
+            table (str): The table to upsert into
+            keyvalues (dict): The unique key tables and their new values
+            values (dict): The nonunique columns and their new values
+            insertion_values (dict): additional key/values to use only when
+                inserting
+            lock (bool): True to lock the table when doing the upsert.
+        Returns:
+            bool: Return True if a new entry was created, False if an existing
+            one was updated.
+        """
         # We need to lock the table :(, unless we're *really* careful
         if lock:
             self.database_engine.lock_table(txn, table)
 
+        def _getwhere(key):
+            # If the value we're passing in is None (aka NULL), we need to use
+            # IS, not =, as NULL = NULL equals NULL (False).
+            if keyvalues[key] is None:
+                return "%s IS ?" % (key,)
+            else:
+                return "%s = ?" % (key,)
+
         # First try to update.
         sql = "UPDATE %s SET %s WHERE %s" % (
             table,
             ", ".join("%s = ?" % (k,) for k in values),
-            " AND ".join("%s = ?" % (k,) for k in keyvalues)
+            " AND ".join(_getwhere(k) for k in keyvalues)
         )
         sqlargs = list(values.values()) + list(keyvalues.values())
 
@@ -569,12 +700,44 @@ class SQLBaseStore(object):
         sql = "INSERT INTO %s (%s) VALUES (%s)" % (
             table,
             ", ".join(k for k in allvalues),
-            ", ".join("?" for _ in allvalues)
+            ", ".join("?" for _ in allvalues),
         )
         txn.execute(sql, list(allvalues.values()))
         # successfully inserted
         return True
 
+    def _simple_upsert_txn_native_upsert(
+        self, txn, table, keyvalues, values, insertion_values={}
+    ):
+        """
+        Use the native UPSERT functionality in recent PostgreSQL versions.
+
+        Args:
+            table (str): The table to upsert into
+            keyvalues (dict): The unique key tables and their new values
+            values (dict): The nonunique columns and their new values
+            insertion_values (dict): additional key/values to use only when
+                inserting
+        Returns:
+            None
+        """
+        allvalues = {}
+        allvalues.update(keyvalues)
+        allvalues.update(values)
+        allvalues.update(insertion_values)
+
+        sql = (
+            "INSERT INTO %s (%s) VALUES (%s) "
+            "ON CONFLICT (%s) DO UPDATE SET %s"
+        ) % (
+            table,
+            ", ".join(k for k in allvalues),
+            ", ".join("?" for _ in allvalues),
+            ", ".join(k for k in keyvalues),
+            ", ".join(k + "=EXCLUDED." + k for k in values),
+        )
+        txn.execute(sql, list(allvalues.values()))
+
     def _simple_select_one(self, table, keyvalues, retcols,
                            allow_none=False, desc="_simple_select_one"):
         """Executes a SELECT query on the named table, which is expected to
diff --git a/synapse/storage/background_updates.py b/synapse/storage/background_updates.py
index 5fe1ca2d..60cdc884 100644
--- a/synapse/storage/background_updates.py
+++ b/synapse/storage/background_updates.py
@@ -240,7 +240,7 @@ class BackgroundUpdateStore(SQLBaseStore):
         * An integer count of the number of items to update in this batch.
 
         The handler should return a deferred integer count of items updated.
-        The hander is responsible for updating the progress of the update.
+        The handler is responsible for updating the progress of the update.
 
         Args:
             update_name(str): The name of the update that this code handles.
diff --git a/synapse/storage/client_ips.py b/synapse/storage/client_ips.py
index 9ad17b7c..091d7116 100644
--- a/synapse/storage/client_ips.py
+++ b/synapse/storage/client_ips.py
@@ -65,7 +65,27 @@ class ClientIpStore(background_updates.BackgroundUpdateStore):
             columns=["last_seen"],
         )
 
-        # (user_id, access_token, ip) -> (user_agent, device_id, last_seen)
+        self.register_background_update_handler(
+            "user_ips_remove_dupes",
+            self._remove_user_ip_dupes,
+        )
+
+        # Register a unique index
+        self.register_background_index_update(
+            "user_ips_device_unique_index",
+            index_name="user_ips_user_token_ip_unique_index",
+            table="user_ips",
+            columns=["user_id", "access_token", "ip"],
+            unique=True,
+        )
+
+        # Drop the old non-unique index
+        self.register_background_update_handler(
+            "user_ips_drop_nonunique_index",
+            self._remove_user_ip_nonunique,
+        )
+
+        # (user_id, access_token, ip,) -> (user_agent, device_id, last_seen)
         self._batch_row_update = {}
 
         self._client_ip_looper = self._clock.looping_call(
@@ -76,6 +96,129 @@ class ClientIpStore(background_updates.BackgroundUpdateStore):
         )
 
     @defer.inlineCallbacks
+    def _remove_user_ip_nonunique(self, progress, batch_size):
+        def f(conn):
+            txn = conn.cursor()
+            txn.execute(
+                "DROP INDEX IF EXISTS user_ips_user_ip"
+            )
+            txn.close()
+
+        yield self.runWithConnection(f)
+        yield self._end_background_update("user_ips_drop_nonunique_index")
+        defer.returnValue(1)
+
+    @defer.inlineCallbacks
+    def _remove_user_ip_dupes(self, progress, batch_size):
+        # This works function works by scanning the user_ips table in batches
+        # based on `last_seen`. For each row in a batch it searches the rest of
+        # the table to see if there are any duplicates, if there are then they
+        # are removed and replaced with a suitable row.
+
+        # Fetch the start of the batch
+        begin_last_seen = progress.get("last_seen", 0)
+
+        def get_last_seen(txn):
+            txn.execute(
+                """
+                SELECT last_seen FROM user_ips
+                WHERE last_seen > ?
+                ORDER BY last_seen
+                LIMIT 1
+                OFFSET ?
+                """,
+                (begin_last_seen, batch_size)
+            )
+            row = txn.fetchone()
+            if row:
+                return row[0]
+            else:
+                return None
+
+        # Get a last seen that has roughly `batch_size` since `begin_last_seen`
+        end_last_seen = yield self.runInteraction(
+            "user_ips_dups_get_last_seen", get_last_seen
+        )
+
+        # If it returns None, then we're processing the last batch
+        last = end_last_seen is None
+
+        logger.info(
+            "Scanning for duplicate 'user_ips' rows in range: %s <= last_seen < %s",
+            begin_last_seen, end_last_seen,
+        )
+
+        def remove(txn):
+            # This works by looking at all entries in the given time span, and
+            # then for each (user_id, access_token, ip) tuple in that range
+            # checking for any duplicates in the rest of the table (via a join).
+            # It then only returns entries which have duplicates, and the max
+            # last_seen across all duplicates, which can the be used to delete
+            # all other duplicates.
+            # It is efficient due to the existence of (user_id, access_token,
+            # ip) and (last_seen) indices.
+
+            # Define the search space, which requires handling the last batch in
+            # a different way
+            if last:
+                clause = "? <= last_seen"
+                args = (begin_last_seen,)
+            else:
+                clause = "? <= last_seen AND last_seen < ?"
+                args = (begin_last_seen, end_last_seen)
+
+            txn.execute(
+                """
+                SELECT user_id, access_token, ip,
+                       MAX(device_id), MAX(user_agent), MAX(last_seen)
+                FROM (
+                    SELECT user_id, access_token, ip
+                    FROM user_ips
+                    WHERE {}
+                ) c
+                INNER JOIN user_ips USING (user_id, access_token, ip)
+                GROUP BY user_id, access_token, ip
+                HAVING count(*) > 1
+                """.format(clause),
+                args
+            )
+            res = txn.fetchall()
+
+            # We've got some duplicates
+            for i in res:
+                user_id, access_token, ip, device_id, user_agent, last_seen = i
+
+                # Drop all the duplicates
+                txn.execute(
+                    """
+                    DELETE FROM user_ips
+                    WHERE user_id = ? AND access_token = ? AND ip = ?
+                    """,
+                    (user_id, access_token, ip)
+                )
+
+                # Add in one to be the last_seen
+                txn.execute(
+                    """
+                    INSERT INTO user_ips
+                    (user_id, access_token, ip, device_id, user_agent, last_seen)
+                    VALUES (?, ?, ?, ?, ?, ?)
+                    """,
+                    (user_id, access_token, ip, device_id, user_agent, last_seen)
+                )
+
+            self._background_update_progress_txn(
+                txn, "user_ips_remove_dupes", {"last_seen": end_last_seen}
+            )
+
+        yield self.runInteraction("user_ips_dups_remove", remove)
+
+        if last:
+            yield self._end_background_update("user_ips_remove_dupes")
+
+        defer.returnValue(batch_size)
+
+    @defer.inlineCallbacks
     def insert_client_ip(self, user_id, access_token, ip, user_agent, device_id,
                          now=None):
         if not now:
@@ -114,7 +257,10 @@ class ClientIpStore(background_updates.BackgroundUpdateStore):
         )
 
     def _update_client_ips_batch_txn(self, txn, to_update):
-        self.database_engine.lock_table(txn, "user_ips")
+        if "user_ips" in self._unsafe_to_upsert_tables or (
+            not self.database_engine.can_native_upsert
+        ):
+            self.database_engine.lock_table(txn, "user_ips")
 
         for entry in iteritems(to_update):
             (user_id, access_token, ip), (user_agent, device_id, last_seen) = entry
@@ -127,10 +273,10 @@ class ClientIpStore(background_updates.BackgroundUpdateStore):
                         "user_id": user_id,
                         "access_token": access_token,
                         "ip": ip,
-                        "user_agent": user_agent,
-                        "device_id": device_id,
                     },
                     values={
+                        "user_agent": user_agent,
+                        "device_id": device_id,
                         "last_seen": last_seen,
                     },
                     lock=False,
@@ -227,7 +373,7 @@ class ClientIpStore(background_updates.BackgroundUpdateStore):
         results = {}
 
         for key in self._batch_row_update:
-            uid, access_token, ip = key
+            uid, access_token, ip, = key
             if uid == user_id:
                 user_agent, _, last_seen = self._batch_row_update[key]
                 results[(access_token, ip)] = (user_agent, last_seen)
diff --git a/synapse/storage/engines/__init__.py b/synapse/storage/engines/__init__.py
index e2f9de84..ff5ef97c 100644
--- a/synapse/storage/engines/__init__.py
+++ b/synapse/storage/engines/__init__.py
@@ -18,7 +18,7 @@ import platform
 
 from ._base import IncorrectDatabaseSetup
 from .postgres import PostgresEngine
-from .sqlite3 import Sqlite3Engine
+from .sqlite import Sqlite3Engine
 
 SUPPORTED_MODULE = {
     "sqlite3": Sqlite3Engine,
diff --git a/synapse/storage/engines/postgres.py b/synapse/storage/engines/postgres.py
index 42225f8a..4004427c 100644
--- a/synapse/storage/engines/postgres.py
+++ b/synapse/storage/engines/postgres.py
@@ -38,6 +38,13 @@ class PostgresEngine(object):
         return sql.replace("?", "%s")
 
     def on_new_connection(self, db_conn):
+
+        # Get the version of PostgreSQL that we're using. As per the psycopg2
+        # docs: The number is formed by converting the major, minor, and
+        # revision numbers into two-decimal-digit numbers and appending them
+        # together. For example, version 8.1.5 will be returned as 80105
+        self._version = db_conn.server_version
+
         db_conn.set_isolation_level(
             self.module.extensions.ISOLATION_LEVEL_REPEATABLE_READ
         )
@@ -54,6 +61,13 @@ class PostgresEngine(object):
 
         cursor.close()
 
+    @property
+    def can_native_upsert(self):
+        """
+        Can we use native UPSERTs? This requires PostgreSQL 9.5+.
+        """
+        return self._version >= 90500
+
     def is_deadlock(self, error):
         if isinstance(error, self.module.DatabaseError):
             # https://www.postgresql.org/docs/current/static/errcodes-appendix.html
diff --git a/synapse/storage/engines/sqlite3.py b/synapse/storage/engines/sqlite.py
index 19949fc4..059ab810 100644
--- a/synapse/storage/engines/sqlite3.py
+++ b/synapse/storage/engines/sqlite.py
@@ -30,6 +30,14 @@ class Sqlite3Engine(object):
         self._current_state_group_id = None
         self._current_state_group_id_lock = threading.Lock()
 
+    @property
+    def can_native_upsert(self):
+        """
+        Do we support native UPSERTs? This requires SQLite3 3.24+, plus some
+        more work we haven't done yet to tell what was inserted vs updated.
+        """
+        return self.module.sqlite_version_info >= (3, 24, 0)
+
     def check_database(self, txn):
         pass
 
diff --git a/synapse/storage/event_federation.py b/synapse/storage/event_federation.py
index d3b9dea1..38809ed0 100644
--- a/synapse/storage/event_federation.py
+++ b/synapse/storage/event_federation.py
@@ -125,6 +125,29 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore,
 
         return dict(txn)
 
+    @defer.inlineCallbacks
+    def get_max_depth_of(self, event_ids):
+        """Returns the max depth of a set of event IDs
+
+        Args:
+            event_ids (list[str])
+
+        Returns
+            Deferred[int]
+        """
+        rows = yield self._simple_select_many_batch(
+            table="events",
+            column="event_id",
+            iterable=event_ids,
+            retcols=("depth",),
+            desc="get_max_depth_of",
+        )
+
+        if not rows:
+            defer.returnValue(0)
+        else:
+            defer.returnValue(max(row["depth"] for row in rows))
+
     def _get_oldest_events_in_room_txn(self, txn, room_id):
         return self._simple_select_onecol_txn(
             txn,
diff --git a/synapse/storage/events.py b/synapse/storage/events.py
index 2047110b..81b25048 100644
--- a/synapse/storage/events.py
+++ b/synapse/storage/events.py
@@ -739,7 +739,18 @@ class EventsStore(StateGroupWorkerStore, EventFederationStore, EventsWorkerStore
         }
 
         events_map = {ev.event_id: ev for ev, _ in events_context}
-        room_version = yield self.get_room_version(room_id)
+
+        # We need to get the room version, which is in the create event.
+        # Normally that'd be in the database, but its also possible that we're
+        # currently trying to persist it.
+        room_version = None
+        for ev, _ in events_context:
+            if ev.type == EventTypes.Create and ev.state_key == "":
+                room_version = ev.content.get("room_version", "1")
+                break
+
+        if not room_version:
+            room_version = yield self.get_room_version(room_id)
 
         logger.debug("calling resolve_state_groups from preserve_events")
         res = yield self._state_resolution_handler.resolve_state_groups(
@@ -893,106 +904,106 @@ class EventsStore(StateGroupWorkerStore, EventFederationStore, EventsWorkerStore
 
     def _update_current_state_txn(self, txn, state_delta_by_room, max_stream_order):
         for room_id, current_state_tuple in iteritems(state_delta_by_room):
-                to_delete, to_insert = current_state_tuple
-
-                # First we add entries to the current_state_delta_stream. We
-                # do this before updating the current_state_events table so
-                # that we can use it to calculate the `prev_event_id`. (This
-                # allows us to not have to pull out the existing state
-                # unnecessarily).
-                sql = """
-                    INSERT INTO current_state_delta_stream
-                    (stream_id, room_id, type, state_key, event_id, prev_event_id)
-                    SELECT ?, ?, ?, ?, ?, (
-                        SELECT event_id FROM current_state_events
-                        WHERE room_id = ? AND type = ? AND state_key = ?
-                    )
-                """
-                txn.executemany(sql, (
-                    (
-                        max_stream_order, room_id, etype, state_key, None,
-                        room_id, etype, state_key,
-                    )
-                    for etype, state_key in to_delete
-                    # We sanity check that we're deleting rather than updating
-                    if (etype, state_key) not in to_insert
-                ))
-                txn.executemany(sql, (
-                    (
-                        max_stream_order, room_id, etype, state_key, ev_id,
-                        room_id, etype, state_key,
-                    )
-                    for (etype, state_key), ev_id in iteritems(to_insert)
-                ))
+            to_delete, to_insert = current_state_tuple
 
-                # Now we actually update the current_state_events table
-
-                txn.executemany(
-                    "DELETE FROM current_state_events"
-                    " WHERE room_id = ? AND type = ? AND state_key = ?",
-                    (
-                        (room_id, etype, state_key)
-                        for etype, state_key in itertools.chain(to_delete, to_insert)
-                    ),
+            # First we add entries to the current_state_delta_stream. We
+            # do this before updating the current_state_events table so
+            # that we can use it to calculate the `prev_event_id`. (This
+            # allows us to not have to pull out the existing state
+            # unnecessarily).
+            sql = """
+                INSERT INTO current_state_delta_stream
+                (stream_id, room_id, type, state_key, event_id, prev_event_id)
+                SELECT ?, ?, ?, ?, ?, (
+                    SELECT event_id FROM current_state_events
+                    WHERE room_id = ? AND type = ? AND state_key = ?
                 )
-
-                self._simple_insert_many_txn(
-                    txn,
-                    table="current_state_events",
-                    values=[
-                        {
-                            "event_id": ev_id,
-                            "room_id": room_id,
-                            "type": key[0],
-                            "state_key": key[1],
-                        }
-                        for key, ev_id in iteritems(to_insert)
-                    ],
+            """
+            txn.executemany(sql, (
+                (
+                    max_stream_order, room_id, etype, state_key, None,
+                    room_id, etype, state_key,
                 )
-
-                txn.call_after(
-                    self._curr_state_delta_stream_cache.entity_has_changed,
-                    room_id, max_stream_order,
+                for etype, state_key in to_delete
+                # We sanity check that we're deleting rather than updating
+                if (etype, state_key) not in to_insert
+            ))
+            txn.executemany(sql, (
+                (
+                    max_stream_order, room_id, etype, state_key, ev_id,
+                    room_id, etype, state_key,
                 )
+                for (etype, state_key), ev_id in iteritems(to_insert)
+            ))
 
-                # Invalidate the various caches
-
-                # Figure out the changes of membership to invalidate the
-                # `get_rooms_for_user` cache.
-                # We find out which membership events we may have deleted
-                # and which we have added, then we invlidate the caches for all
-                # those users.
-                members_changed = set(
-                    state_key
-                    for ev_type, state_key in itertools.chain(to_delete, to_insert)
-                    if ev_type == EventTypes.Member
-                )
+            # Now we actually update the current_state_events table
 
-                for member in members_changed:
-                    self._invalidate_cache_and_stream(
-                        txn, self.get_rooms_for_user_with_stream_ordering, (member,)
-                    )
+            txn.executemany(
+                "DELETE FROM current_state_events"
+                " WHERE room_id = ? AND type = ? AND state_key = ?",
+                (
+                    (room_id, etype, state_key)
+                    for etype, state_key in itertools.chain(to_delete, to_insert)
+                ),
+            )
 
-                for host in set(get_domain_from_id(u) for u in members_changed):
-                    self._invalidate_cache_and_stream(
-                        txn, self.is_host_joined, (room_id, host)
-                    )
-                    self._invalidate_cache_and_stream(
-                        txn, self.was_host_joined, (room_id, host)
-                    )
+            self._simple_insert_many_txn(
+                txn,
+                table="current_state_events",
+                values=[
+                    {
+                        "event_id": ev_id,
+                        "room_id": room_id,
+                        "type": key[0],
+                        "state_key": key[1],
+                    }
+                    for key, ev_id in iteritems(to_insert)
+                ],
+            )
+
+            txn.call_after(
+                self._curr_state_delta_stream_cache.entity_has_changed,
+                room_id, max_stream_order,
+            )
+
+            # Invalidate the various caches
+
+            # Figure out the changes of membership to invalidate the
+            # `get_rooms_for_user` cache.
+            # We find out which membership events we may have deleted
+            # and which we have added, then we invlidate the caches for all
+            # those users.
+            members_changed = set(
+                state_key
+                for ev_type, state_key in itertools.chain(to_delete, to_insert)
+                if ev_type == EventTypes.Member
+            )
 
+            for member in members_changed:
                 self._invalidate_cache_and_stream(
-                    txn, self.get_users_in_room, (room_id,)
+                    txn, self.get_rooms_for_user_with_stream_ordering, (member,)
                 )
 
+            for host in set(get_domain_from_id(u) for u in members_changed):
                 self._invalidate_cache_and_stream(
-                    txn, self.get_room_summary, (room_id,)
+                    txn, self.is_host_joined, (room_id, host)
                 )
-
                 self._invalidate_cache_and_stream(
-                    txn, self.get_current_state_ids, (room_id,)
+                    txn, self.was_host_joined, (room_id, host)
                 )
 
+            self._invalidate_cache_and_stream(
+                txn, self.get_users_in_room, (room_id,)
+            )
+
+            self._invalidate_cache_and_stream(
+                txn, self.get_room_summary, (room_id,)
+            )
+
+            self._invalidate_cache_and_stream(
+                txn, self.get_current_state_ids, (room_id,)
+            )
+
     def _update_forward_extremities_txn(self, txn, new_forward_extremities,
                                         max_stream_order):
         for room_id, new_extrem in iteritems(new_forward_extremities):
@@ -1257,6 +1268,7 @@ class EventsStore(StateGroupWorkerStore, EventFederationStore, EventsWorkerStore
                         event.internal_metadata.get_dict()
                     ),
                     "json": encode_json(event_dict(event)),
+                    "format_version": event.format_version,
                 }
                 for event, _ in events_and_contexts
             ],
diff --git a/synapse/storage/events_worker.py b/synapse/storage/events_worker.py
index a8326f52..1716be52 100644
--- a/synapse/storage/events_worker.py
+++ b/synapse/storage/events_worker.py
@@ -21,13 +21,14 @@ from canonicaljson import json
 
 from twisted.internet import defer
 
+from synapse.api.constants import EventFormatVersions, EventTypes
 from synapse.api.errors import NotFoundError
+from synapse.events import FrozenEvent, event_type_from_format_version  # noqa: F401
 # these are only included to make the type annotations work
-from synapse.events import EventBase  # noqa: F401
-from synapse.events import FrozenEvent
 from synapse.events.snapshot import EventContext  # noqa: F401
 from synapse.events.utils import prune_event
 from synapse.metrics.background_process_metrics import run_as_background_process
+from synapse.types import get_domain_from_id
 from synapse.util.logcontext import (
     LoggingContext,
     PreserveLoggingContext,
@@ -160,9 +161,14 @@ class EventsWorkerStore(SQLBaseStore):
             log_ctx = LoggingContext.current_context()
             log_ctx.record_event_fetch(len(missing_events_ids))
 
+            # Note that _enqueue_events is also responsible for turning db rows
+            # into FrozenEvents (via _get_event_from_row), which involves seeing if
+            # the events have been redacted, and if so pulling the redaction event out
+            # of the database to check it.
+            #
+            # _enqueue_events is a bit of a rubbish name but naming is hard.
             missing_events = yield self._enqueue_events(
                 missing_events_ids,
-                check_redacted=check_redacted,
                 allow_rejected=allow_rejected,
             )
 
@@ -174,6 +180,50 @@ class EventsWorkerStore(SQLBaseStore):
             if not entry:
                 continue
 
+            # Starting in room version v3, some redactions need to be rechecked if we
+            # didn't have the redacted event at the time, so we recheck on read
+            # instead.
+            if not allow_rejected and entry.event.type == EventTypes.Redaction:
+                if entry.event.internal_metadata.need_to_check_redaction():
+                    # XXX: we need to avoid calling get_event here.
+                    #
+                    # The problem is that we end up at this point when an event
+                    # which has been redacted is pulled out of the database by
+                    # _enqueue_events, because _enqueue_events needs to check the
+                    # redaction before it can cache the redacted event. So obviously,
+                    # calling get_event to get the redacted event out of the database
+                    # gives us an infinite loop.
+                    #
+                    # For now (quick hack to fix during 0.99 release cycle), we just
+                    # go and fetch the relevant row from the db, but it would be nice
+                    # to think about how we can cache this rather than hit the db
+                    # every time we access a redaction event.
+                    #
+                    # One thought on how to do this:
+                    #  1. split _get_events up so that it is divided into (a) get the
+                    #     rawish event from the db/cache, (b) do the redaction/rejection
+                    #     filtering
+                    #  2. have _get_event_from_row just call the first half of that
+
+                    orig_sender = yield self._simple_select_one_onecol(
+                        table="events",
+                        keyvalues={"event_id": entry.event.redacts},
+                        retcol="sender",
+                        allow_none=True,
+                    )
+
+                    expected_domain = get_domain_from_id(entry.event.sender)
+                    if orig_sender and get_domain_from_id(orig_sender) == expected_domain:
+                        # This redaction event is allowed. Mark as not needing a
+                        # recheck.
+                        entry.event.internal_metadata.recheck_redaction = False
+                    else:
+                        # We don't have the event that is being redacted, so we
+                        # assume that the event isn't authorized for now. (If we
+                        # later receive the event, then we will always redact
+                        # it anyway, since we have this redaction)
+                        continue
+
             if allow_rejected or not entry.event.rejected_reason:
                 if check_redacted and entry.redacted_event:
                     event = entry.redacted_event
@@ -197,7 +247,7 @@ class EventsWorkerStore(SQLBaseStore):
         defer.returnValue(events)
 
     def _invalidate_get_event_cache(self, event_id):
-            self._get_event_cache.invalidate((event_id,))
+        self._get_event_cache.invalidate((event_id,))
 
     def _get_events_from_cache(self, events, allow_rejected, update_metrics=True):
         """Fetch events from the caches
@@ -310,7 +360,7 @@ class EventsWorkerStore(SQLBaseStore):
                     self.hs.get_reactor().callFromThread(fire, event_list, e)
 
     @defer.inlineCallbacks
-    def _enqueue_events(self, events, check_redacted=True, allow_rejected=False):
+    def _enqueue_events(self, events, allow_rejected=False):
         """Fetches events from the database using the _event_fetch_list. This
         allows batch and bulk fetching of events - it allows us to fetch events
         without having to create a new transaction for each request for events.
@@ -353,6 +403,7 @@ class EventsWorkerStore(SQLBaseStore):
                     self._get_event_from_row,
                     row["internal_metadata"], row["json"], row["redacts"],
                     rejected_reason=row["rejects"],
+                    format_version=row["format_version"],
                 )
                 for row in rows
             ],
@@ -377,6 +428,7 @@ class EventsWorkerStore(SQLBaseStore):
                 " e.event_id as event_id, "
                 " e.internal_metadata,"
                 " e.json,"
+                " e.format_version, "
                 " r.redacts as redacts,"
                 " rej.event_id as rejects "
                 " FROM event_json as e"
@@ -392,7 +444,7 @@ class EventsWorkerStore(SQLBaseStore):
 
     @defer.inlineCallbacks
     def _get_event_from_row(self, internal_metadata, js, redacted,
-                            rejected_reason=None):
+                            format_version, rejected_reason=None):
         with Measure(self._clock, "_get_event_from_row"):
             d = json.loads(js)
             internal_metadata = json.loads(internal_metadata)
@@ -405,8 +457,13 @@ class EventsWorkerStore(SQLBaseStore):
                     desc="_get_event_from_row_rejected_reason",
                 )
 
-            original_ev = FrozenEvent(
-                d,
+            if format_version is None:
+                # This means that we stored the event before we had the concept
+                # of a event format version, so it must be a V1 event.
+                format_version = EventFormatVersions.V1
+
+            original_ev = event_type_from_format_version(format_version)(
+                event_dict=d,
                 internal_metadata_dict=internal_metadata,
                 rejected_reason=rejected_reason,
             )
@@ -436,6 +493,19 @@ class EventsWorkerStore(SQLBaseStore):
                     # will serialise this field correctly
                     redacted_event.unsigned["redacted_because"] = because
 
+                    # Starting in room version v3, some redactions need to be
+                    # rechecked if we didn't have the redacted event at the
+                    # time, so we recheck on read instead.
+                    if because.internal_metadata.need_to_check_redaction():
+                        expected_domain = get_domain_from_id(original_ev.sender)
+                        if get_domain_from_id(because.sender) == expected_domain:
+                            # This redaction event is allowed. Mark as not needing a
+                            # recheck.
+                            because.internal_metadata.recheck_redaction = False
+                        else:
+                            # Senders don't match, so the event isn't actually redacted
+                            redacted_event = None
+
             cache_entry = _EventCacheEntry(
                 event=original_ev,
                 redacted_event=redacted_event,
diff --git a/synapse/storage/monthly_active_users.py b/synapse/storage/monthly_active_users.py
index d6fc8edd..9e7e09b8 100644
--- a/synapse/storage/monthly_active_users.py
+++ b/synapse/storage/monthly_active_users.py
@@ -197,15 +197,21 @@ class MonthlyActiveUsersStore(SQLBaseStore):
         if is_support:
             return
 
-        is_insert = yield self.runInteraction(
+        yield self.runInteraction(
             "upsert_monthly_active_user", self.upsert_monthly_active_user_txn,
             user_id
         )
 
-        if is_insert:
-            self.user_last_seen_monthly_active.invalidate((user_id,))
+        user_in_mau = self.user_last_seen_monthly_active.cache.get(
+            (user_id,),
+            None,
+            update_metrics=False
+        )
+        if user_in_mau is None:
             self.get_monthly_active_count.invalidate(())
 
+        self.user_last_seen_monthly_active.invalidate((user_id,))
+
     def upsert_monthly_active_user_txn(self, txn, user_id):
         """Updates or inserts monthly active user member
 
diff --git a/synapse/storage/pusher.py b/synapse/storage/pusher.py
index 2743b52b..134297e2 100644
--- a/synapse/storage/pusher.py
+++ b/synapse/storage/pusher.py
@@ -215,7 +215,7 @@ class PusherStore(PusherWorkerStore):
         with self._pushers_id_gen.get_next() as stream_id:
             # no need to lock because `pushers` has a unique key on
             # (app_id, pushkey, user_name) so _simple_upsert will retry
-            newly_inserted = yield self._simple_upsert(
+            yield self._simple_upsert(
                 table="pushers",
                 keyvalues={
                     "app_id": app_id,
@@ -238,7 +238,12 @@ class PusherStore(PusherWorkerStore):
                 lock=False,
             )
 
-            if newly_inserted:
+            user_has_pusher = self.get_if_user_has_pusher.cache.get(
+                (user_id,), None, update_metrics=False
+            )
+
+            if user_has_pusher is not True:
+                # invalidate, since we the user might not have had a pusher before
                 yield self.runInteraction(
                     "add_pusher",
                     self._invalidate_cache_and_stream,
diff --git a/synapse/storage/roommember.py b/synapse/storage/roommember.py
index 0707f9a8..592c1bcd 100644
--- a/synapse/storage/roommember.py
+++ b/synapse/storage/roommember.py
@@ -588,12 +588,12 @@ class RoomMemberStore(RoomMemberWorkerStore):
             )
 
             # We update the local_invites table only if the event is "current",
-            # i.e., its something that has just happened.
-            # The only current event that can also be an outlier is if its an
-            # invite that has come in across federation.
+            # i.e., its something that has just happened. If the event is an
+            # outlier it is only current if its an "out of band membership",
+            # like a remote invite or a rejection of a remote invite.
             is_new_state = not backfilled and (
                 not event.internal_metadata.is_outlier()
-                or event.internal_metadata.is_invite_from_remote()
+                or event.internal_metadata.is_out_of_band_membership()
             )
             is_mine = self.hs.is_mine_id(event.state_key)
             if is_new_state and is_mine:
diff --git a/synapse/storage/schema/delta/53/event_format_version.sql b/synapse/storage/schema/delta/53/event_format_version.sql
new file mode 100644
index 00000000..1d977c28
--- /dev/null
+++ b/synapse/storage/schema/delta/53/event_format_version.sql
@@ -0,0 +1,16 @@
+/* Copyright 2019 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ALTER TABLE event_json ADD COLUMN format_version INTEGER;
diff --git a/synapse/storage/schema/delta/53/user_ips_index.sql b/synapse/storage/schema/delta/53/user_ips_index.sql
new file mode 100644
index 00000000..4ca346c1
--- /dev/null
+++ b/synapse/storage/schema/delta/53/user_ips_index.sql
@@ -0,0 +1,26 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- delete duplicates
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('user_ips_remove_dupes', '{}');
+
+-- add a new unique index to user_ips table
+INSERT INTO background_updates (update_name, progress_json, depends_on) VALUES
+  ('user_ips_device_unique_index', '{}', 'user_ips_remove_dupes');
+
+-- drop the old original index
+INSERT INTO background_updates (update_name, progress_json, depends_on) VALUES
+  ('user_ips_drop_nonunique_index', '{}', 'user_ips_device_unique_index');
\ No newline at end of file
diff --git a/synapse/storage/state.py b/synapse/storage/state.py
index a134e9b3..c3ab7db7 100644
--- a/synapse/storage/state.py
+++ b/synapse/storage/state.py
@@ -437,6 +437,30 @@ class StateGroupWorkerStore(EventsWorkerStore, SQLBaseStore):
         create_event = yield self.get_event(create_id)
         defer.returnValue(create_event.content.get("room_version", "1"))
 
+    @defer.inlineCallbacks
+    def get_room_predecessor(self, room_id):
+        """Get the predecessor room of an upgraded room if one exists.
+        Otherwise return None.
+
+        Args:
+            room_id (str)
+
+        Returns:
+            Deferred[unicode|None]: predecessor room id
+        """
+        state_ids = yield self.get_current_state_ids(room_id)
+        create_id = state_ids.get((EventTypes.Create, ""))
+
+        # If we can't find the create event, assume we've hit a dead end
+        if not create_id:
+            defer.returnValue(None)
+
+        # Retrieve the room's create event
+        create_event = yield self.get_event(create_id)
+
+        # Return predecessor if present
+        defer.returnValue(create_event.content.get("predecessor", None))
+
     @cached(max_entries=100000, iterable=True)
     def get_current_state_ids(self, room_id):
         """Get the current state event ids for a room based on the
diff --git a/synapse/storage/user_directory.py b/synapse/storage/user_directory.py
index a8781b0e..ce482122 100644
--- a/synapse/storage/user_directory.py
+++ b/synapse/storage/user_directory.py
@@ -168,14 +168,14 @@ class UserDirectoryStore(SQLBaseStore):
             if isinstance(self.database_engine, PostgresEngine):
                 # We weight the localpart most highly, then display name and finally
                 # server name
-                if new_entry:
+                if self.database_engine.can_native_upsert:
                     sql = """
                         INSERT INTO user_directory_search(user_id, vector)
                         VALUES (?,
                             setweight(to_tsvector('english', ?), 'A')
                             || setweight(to_tsvector('english', ?), 'D')
                             || setweight(to_tsvector('english', COALESCE(?, '')), 'B')
-                        )
+                        ) ON CONFLICT (user_id) DO UPDATE SET vector=EXCLUDED.vector
                     """
                     txn.execute(
                         sql,
@@ -185,20 +185,45 @@ class UserDirectoryStore(SQLBaseStore):
                         )
                     )
                 else:
-                    sql = """
-                        UPDATE user_directory_search
-                        SET vector = setweight(to_tsvector('english', ?), 'A')
-                            || setweight(to_tsvector('english', ?), 'D')
-                            || setweight(to_tsvector('english', COALESCE(?, '')), 'B')
-                        WHERE user_id = ?
-                    """
-                    txn.execute(
-                        sql,
-                        (
-                            get_localpart_from_id(user_id), get_domain_from_id(user_id),
-                            display_name, user_id,
+                    # TODO: Remove this code after we've bumped the minimum version
+                    # of postgres to always support upserts, so we can get rid of
+                    # `new_entry` usage
+                    if new_entry is True:
+                        sql = """
+                            INSERT INTO user_directory_search(user_id, vector)
+                            VALUES (?,
+                                setweight(to_tsvector('english', ?), 'A')
+                                || setweight(to_tsvector('english', ?), 'D')
+                                || setweight(to_tsvector('english', COALESCE(?, '')), 'B')
+                            )
+                        """
+                        txn.execute(
+                            sql,
+                            (
+                                user_id, get_localpart_from_id(user_id),
+                                get_domain_from_id(user_id), display_name,
+                            )
+                        )
+                    elif new_entry is False:
+                        sql = """
+                            UPDATE user_directory_search
+                            SET vector = setweight(to_tsvector('english', ?), 'A')
+                                || setweight(to_tsvector('english', ?), 'D')
+                                || setweight(to_tsvector('english', COALESCE(?, '')), 'B')
+                            WHERE user_id = ?
+                        """
+                        txn.execute(
+                            sql,
+                            (
+                                get_localpart_from_id(user_id),
+                                get_domain_from_id(user_id),
+                                display_name, user_id,
+                            )
+                        )
+                    else:
+                        raise RuntimeError(
+                            "upsert returned None when 'can_native_upsert' is False"
                         )
-                    )
             elif isinstance(self.database_engine, Sqlite3Engine):
                 value = "%s %s" % (user_id, display_name,) if display_name else user_id
                 self._simple_upsert_txn(
diff --git a/synapse/util/async_helpers.py b/synapse/util/async_helpers.py
index ec7b2c96..f0e4a0e1 100644
--- a/synapse/util/async_helpers.py
+++ b/synapse/util/async_helpers.py
@@ -201,7 +201,7 @@ class Linearizer(object):
         if entry[0] >= self.max_count:
             res = self._await_lock(key)
         else:
-            logger.info(
+            logger.debug(
                 "Acquired uncontended linearizer lock %r for key %r", self.name, key,
             )
             entry[0] += 1
@@ -215,7 +215,7 @@ class Linearizer(object):
             try:
                 yield
             finally:
-                logger.info("Releasing linearizer lock %r for key %r", self.name, key)
+                logger.debug("Releasing linearizer lock %r for key %r", self.name, key)
 
                 # We've finished executing so check if there are any things
                 # blocked waiting to execute and start one of them
@@ -247,7 +247,7 @@ class Linearizer(object):
         """
         entry = self.key_to_defer[key]
 
-        logger.info(
+        logger.debug(
             "Waiting to acquire linearizer lock %r for key %r", self.name, key,
         )
 
@@ -255,7 +255,7 @@ class Linearizer(object):
         entry[1][new_defer] = 1
 
         def cb(_r):
-            logger.info("Acquired linearizer lock %r for key %r", self.name, key)
+            logger.debug("Acquired linearizer lock %r for key %r", self.name, key)
             entry[0] += 1
 
             # if the code holding the lock completes synchronously, then it
@@ -273,7 +273,7 @@ class Linearizer(object):
         def eb(e):
             logger.info("defer %r got err %r", new_defer, e)
             if isinstance(e, CancelledError):
-                logger.info(
+                logger.debug(
                     "Cancelling wait for linearizer lock %r for key %r",
                     self.name, key,
                 )
@@ -387,12 +387,14 @@ def timeout_deferred(deferred, timeout, reactor, on_timeout_cancel=None):
     deferred that wraps and times out the given deferred, correctly handling
     the case where the given deferred's canceller throws.
 
+    (See https://twistedmatrix.com/trac/ticket/9534)
+
     NOTE: Unlike `Deferred.addTimeout`, this function returns a new deferred
 
     Args:
         deferred (Deferred)
         timeout (float): Timeout in seconds
-        reactor (twisted.internet.reactor): The twisted reactor to use
+        reactor (twisted.interfaces.IReactorTime): The twisted reactor to use
         on_timeout_cancel (callable): A callable which is called immediately
             after the deferred times out, and not if this deferred is
             otherwise cancelled before the timeout.
diff --git a/synapse/util/caches/ttlcache.py b/synapse/util/caches/ttlcache.py
new file mode 100644
index 00000000..5ba18625
--- /dev/null
+++ b/synapse/util/caches/ttlcache.py
@@ -0,0 +1,161 @@
+# -*- coding: utf-8 -*-
+# Copyright 2015, 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+import time
+
+import attr
+from sortedcontainers import SortedList
+
+from synapse.util.caches import register_cache
+
+logger = logging.getLogger(__name__)
+
+SENTINEL = object()
+
+
+class TTLCache(object):
+    """A key/value cache implementation where each entry has its own TTL"""
+
+    def __init__(self, cache_name, timer=time.time):
+        # map from key to _CacheEntry
+        self._data = {}
+
+        # the _CacheEntries, sorted by expiry time
+        self._expiry_list = SortedList()
+
+        self._timer = timer
+
+        self._metrics = register_cache("ttl", cache_name, self)
+
+    def set(self, key, value, ttl):
+        """Add/update an entry in the cache
+
+        Args:
+            key: key for this entry
+            value: value for this entry
+            ttl (float): TTL for this entry, in seconds
+        """
+        expiry = self._timer() + ttl
+
+        self.expire()
+        e = self._data.pop(key, SENTINEL)
+        if e != SENTINEL:
+            self._expiry_list.remove(e)
+
+        entry = _CacheEntry(expiry_time=expiry, key=key, value=value)
+        self._data[key] = entry
+        self._expiry_list.add(entry)
+
+    def get(self, key, default=SENTINEL):
+        """Get a value from the cache
+
+        Args:
+            key: key to look up
+            default: default value to return, if key is not found. If not set, and the
+                key is not found, a KeyError will be raised
+
+        Returns:
+            value from the cache, or the default
+        """
+        self.expire()
+        e = self._data.get(key, SENTINEL)
+        if e == SENTINEL:
+            self._metrics.inc_misses()
+            if default == SENTINEL:
+                raise KeyError(key)
+            return default
+        self._metrics.inc_hits()
+        return e.value
+
+    def get_with_expiry(self, key):
+        """Get a value, and its expiry time, from the cache
+
+        Args:
+            key: key to look up
+
+        Returns:
+            Tuple[Any, float]: the value from the cache, and the expiry time
+
+        Raises:
+            KeyError if the entry is not found
+        """
+        self.expire()
+        try:
+            e = self._data[key]
+        except KeyError:
+            self._metrics.inc_misses()
+            raise
+        self._metrics.inc_hits()
+        return e.value, e.expiry_time
+
+    def pop(self, key, default=SENTINEL):
+        """Remove a value from the cache
+
+        If key is in the cache, remove it and return its value, else return default.
+        If default is not given and key is not in the cache, a KeyError is raised.
+
+        Args:
+            key: key to look up
+            default: default value to return, if key is not found. If not set, and the
+                key is not found, a KeyError will be raised
+
+        Returns:
+            value from the cache, or the default
+        """
+        self.expire()
+        e = self._data.pop(key, SENTINEL)
+        if e == SENTINEL:
+            self._metrics.inc_misses()
+            if default == SENTINEL:
+                raise KeyError(key)
+            return default
+        self._expiry_list.remove(e)
+        self._metrics.inc_hits()
+        return e.value
+
+    def __getitem__(self, key):
+        return self.get(key)
+
+    def __delitem__(self, key):
+        self.pop(key)
+
+    def __contains__(self, key):
+        return key in self._data
+
+    def __len__(self):
+        self.expire()
+        return len(self._data)
+
+    def expire(self):
+        """Run the expiry on the cache. Any entries whose expiry times are due will
+        be removed
+        """
+        now = self._timer()
+        while self._expiry_list:
+            first_entry = self._expiry_list[0]
+            if first_entry.expiry_time - now > 0.0:
+                break
+            del self._data[first_entry.key]
+            del self._expiry_list[0]
+
+
+@attr.s(frozen=True, slots=True)
+class _CacheEntry(object):
+    """TTLCache entry"""
+    # expiry_time is the first attribute, so that entries are sorted by expiry.
+    expiry_time = attr.ib()
+    key = attr.ib()
+    value = attr.ib()
diff --git a/synapse/util/logcontext.py b/synapse/util/logcontext.py
index 4c6e92be..311b49e1 100644
--- a/synapse/util/logcontext.py
+++ b/synapse/util/logcontext.py
@@ -285,7 +285,10 @@ class LoggingContext(object):
         self.alive = False
 
         # if we have a parent, pass our CPU usage stats on
-        if self.parent_context is not None:
+        if (
+            self.parent_context is not None
+            and hasattr(self.parent_context, '_resource_usage')
+        ):
             self.parent_context._resource_usage += self._resource_usage
 
             # reset them in case we get entered again
diff --git a/tests/config/test_generate.py b/tests/config/test_generate.py
index 0c23068b..795b4c29 100644
--- a/tests/config/test_generate.py
+++ b/tests/config/test_generate.py
@@ -50,9 +50,6 @@ class ConfigGenerationTestCase(unittest.TestCase):
                     "homeserver.yaml",
                     "lemurs.win.log.config",
                     "lemurs.win.signing.key",
-                    "lemurs.win.tls.crt",
-                    "lemurs.win.tls.dh",
-                    "lemurs.win.tls.key",
                 ]
             ),
             set(os.listdir(self.dir)),
diff --git a/tests/config/test_tls.py b/tests/config/test_tls.py
new file mode 100644
index 00000000..4ccaf356
--- /dev/null
+++ b/tests/config/test_tls.py
@@ -0,0 +1,75 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import os
+
+from synapse.config.tls import TlsConfig
+
+from tests.unittest import TestCase
+
+
+class TLSConfigTests(TestCase):
+
+    def test_warn_self_signed(self):
+        """
+        Synapse will give a warning when it loads a self-signed certificate.
+        """
+        config_dir = self.mktemp()
+        os.mkdir(config_dir)
+        with open(os.path.join(config_dir, "cert.pem"), 'w') as f:
+            f.write("""-----BEGIN CERTIFICATE-----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=
+-----END CERTIFICATE-----""")
+
+        config = {
+            "tls_certificate_path": os.path.join(config_dir, "cert.pem"),
+            "no_tls": True,
+            "tls_fingerprints": []
+        }
+
+        t = TlsConfig()
+        t.read_config(config)
+        t.read_certificate_from_disk()
+
+        warnings = self.flushWarnings()
+        self.assertEqual(len(warnings), 1)
+        self.assertEqual(
+            warnings[0]["message"],
+            (
+                "Self-signed TLS certificates will not be accepted by "
+                "Synapse 1.0. Please either provide a valid certificate, "
+                "or use Synapse's ACME support to provision one."
+            )
+        )
diff --git a/tests/crypto/test_event_signing.py b/tests/crypto/test_event_signing.py
index b2536c1e..71aa7314 100644
--- a/tests/crypto/test_event_signing.py
+++ b/tests/crypto/test_event_signing.py
@@ -18,7 +18,7 @@ import nacl.signing
 from unpaddedbase64 import decode_base64
 
 from synapse.crypto.event_signing import add_hashes_and_signatures
-from synapse.events.builder import EventBuilder
+from synapse.events import FrozenEvent
 
 from tests import unittest
 
@@ -40,20 +40,18 @@ class EventSigningTestCase(unittest.TestCase):
         self.signing_key.version = KEY_VER
 
     def test_sign_minimal(self):
-        builder = EventBuilder(
-            {
-                'event_id': "$0:domain",
-                'origin': "domain",
-                'origin_server_ts': 1000000,
-                'signatures': {},
-                'type': "X",
-                'unsigned': {'age_ts': 1000000},
-            }
-        )
+        event_dict = {
+            'event_id': "$0:domain",
+            'origin': "domain",
+            'origin_server_ts': 1000000,
+            'signatures': {},
+            'type': "X",
+            'unsigned': {'age_ts': 1000000},
+        }
 
-        add_hashes_and_signatures(builder, HOSTNAME, self.signing_key)
+        add_hashes_and_signatures(event_dict, HOSTNAME, self.signing_key)
 
-        event = builder.build()
+        event = FrozenEvent(event_dict)
 
         self.assertTrue(hasattr(event, 'hashes'))
         self.assertIn('sha256', event.hashes)
@@ -71,23 +69,21 @@ class EventSigningTestCase(unittest.TestCase):
         )
 
     def test_sign_message(self):
-        builder = EventBuilder(
-            {
-                'content': {'body': "Here is the message content"},
-                'event_id': "$0:domain",
-                'origin': "domain",
-                'origin_server_ts': 1000000,
-                'type': "m.room.message",
-                'room_id': "!r:domain",
-                'sender': "@u:domain",
-                'signatures': {},
-                'unsigned': {'age_ts': 1000000},
-            }
-        )
-
-        add_hashes_and_signatures(builder, HOSTNAME, self.signing_key)
-
-        event = builder.build()
+        event_dict = {
+            'content': {'body': "Here is the message content"},
+            'event_id': "$0:domain",
+            'origin': "domain",
+            'origin_server_ts': 1000000,
+            'type': "m.room.message",
+            'room_id': "!r:domain",
+            'sender': "@u:domain",
+            'signatures': {},
+            'unsigned': {'age_ts': 1000000},
+        }
+
+        add_hashes_and_signatures(event_dict, HOSTNAME, self.signing_key)
+
+        event = FrozenEvent(event_dict)
 
         self.assertTrue(hasattr(event, 'hashes'))
         self.assertIn('sha256', event.hashes)
diff --git a/tests/http/__init__.py b/tests/http/__init__.py
index e69de29b..ee8010f5 100644
--- a/tests/http/__init__.py
+++ b/tests/http/__init__.py
@@ -0,0 +1,42 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import os.path
+
+from OpenSSL import SSL
+
+
+def get_test_cert_file():
+    """get the path to the test cert"""
+
+    # the cert file itself is made with:
+    #
+    # openssl req -x509 -newkey rsa:4096 -keyout server.pem  -out server.pem -days 36500 \
+    #     -nodes -subj '/CN=testserv'
+    return os.path.join(
+        os.path.dirname(__file__),
+        'server.pem',
+    )
+
+
+class ServerTLSContext(object):
+    """A TLS Context which presents our test cert."""
+    def __init__(self):
+        self.filename = get_test_cert_file()
+
+    def getContext(self):
+        ctx = SSL.Context(SSL.TLSv1_METHOD)
+        ctx.use_certificate_file(self.filename)
+        ctx.use_privatekey_file(self.filename)
+        return ctx
diff --git a/tests/http/federation/__init__.py b/tests/http/federation/__init__.py
new file mode 100644
index 00000000..1453d045
--- /dev/null
+++ b/tests/http/federation/__init__.py
@@ -0,0 +1,14 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
diff --git a/tests/http/federation/test_matrix_federation_agent.py b/tests/http/federation/test_matrix_federation_agent.py
new file mode 100644
index 00000000..dcf184d3
--- /dev/null
+++ b/tests/http/federation/test_matrix_federation_agent.py
@@ -0,0 +1,991 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import logging
+
+from mock import Mock
+
+import treq
+from zope.interface import implementer
+
+from twisted.internet import defer
+from twisted.internet._sslverify import ClientTLSOptions, OpenSSLCertificateOptions
+from twisted.internet.protocol import Factory
+from twisted.protocols.tls import TLSMemoryBIOFactory
+from twisted.web.http import HTTPChannel
+from twisted.web.http_headers import Headers
+from twisted.web.iweb import IPolicyForHTTPS
+
+from synapse.crypto.context_factory import ClientTLSOptionsFactory
+from synapse.http.federation.matrix_federation_agent import (
+    MatrixFederationAgent,
+    _cache_period_from_headers,
+)
+from synapse.http.federation.srv_resolver import Server
+from synapse.util.caches.ttlcache import TTLCache
+from synapse.util.logcontext import LoggingContext
+
+from tests.http import ServerTLSContext
+from tests.server import FakeTransport, ThreadedMemoryReactorClock
+from tests.unittest import TestCase
+
+logger = logging.getLogger(__name__)
+
+
+class MatrixFederationAgentTests(TestCase):
+    def setUp(self):
+        self.reactor = ThreadedMemoryReactorClock()
+
+        self.mock_resolver = Mock()
+
+        self.well_known_cache = TTLCache("test_cache", timer=self.reactor.seconds)
+
+        self.agent = MatrixFederationAgent(
+            reactor=self.reactor,
+            tls_client_options_factory=ClientTLSOptionsFactory(None),
+            _well_known_tls_policy=TrustingTLSPolicyForHTTPS(),
+            _srv_resolver=self.mock_resolver,
+            _well_known_cache=self.well_known_cache,
+        )
+
+    def _make_connection(self, client_factory, expected_sni):
+        """Builds a test server, and completes the outgoing client connection
+
+        Returns:
+            HTTPChannel: the test server
+        """
+
+        # build the test server
+        server_tls_protocol = _build_test_server()
+
+        # now, tell the client protocol factory to build the client protocol (it will be a
+        # _WrappingProtocol, around a TLSMemoryBIOProtocol, around an
+        # HTTP11ClientProtocol) and wire the output of said protocol up to the server via
+        # a FakeTransport.
+        #
+        # Normally this would be done by the TCP socket code in Twisted, but we are
+        # stubbing that out here.
+        client_protocol = client_factory.buildProtocol(None)
+        client_protocol.makeConnection(
+            FakeTransport(server_tls_protocol, self.reactor, client_protocol),
+        )
+
+        # tell the server tls protocol to send its stuff back to the client, too
+        server_tls_protocol.makeConnection(
+            FakeTransport(client_protocol, self.reactor, server_tls_protocol),
+        )
+
+        # give the reactor a pump to get the TLS juices flowing.
+        self.reactor.pump((0.1,))
+
+        # check the SNI
+        server_name = server_tls_protocol._tlsConnection.get_servername()
+        self.assertEqual(
+            server_name,
+            expected_sni,
+            "Expected SNI %s but got %s" % (expected_sni, server_name),
+        )
+
+        # fish the test server back out of the server-side TLS protocol.
+        return server_tls_protocol.wrappedProtocol
+
+    @defer.inlineCallbacks
+    def _make_get_request(self, uri):
+        """
+        Sends a simple GET request via the agent, and checks its logcontext management
+        """
+        with LoggingContext("one") as context:
+            fetch_d = self.agent.request(b'GET', uri)
+
+            # Nothing happened yet
+            self.assertNoResult(fetch_d)
+
+            # should have reset logcontext to the sentinel
+            _check_logcontext(LoggingContext.sentinel)
+
+            try:
+                fetch_res = yield fetch_d
+                defer.returnValue(fetch_res)
+            except Exception as e:
+                logger.info("Fetch of %s failed: %s", uri.decode("ascii"), e)
+                raise
+            finally:
+                _check_logcontext(context)
+
+    def _handle_well_known_connection(
+        self, client_factory, expected_sni, content, response_headers={},
+    ):
+        """Handle an outgoing HTTPs connection: wire it up to a server, check that the
+        request is for a .well-known, and send the response.
+
+        Args:
+            client_factory (IProtocolFactory): outgoing connection
+            expected_sni (bytes): SNI that we expect the outgoing connection to send
+            content (bytes): content to send back as the .well-known
+        Returns:
+            HTTPChannel: server impl
+        """
+        # make the connection for .well-known
+        well_known_server = self._make_connection(
+            client_factory,
+            expected_sni=expected_sni,
+        )
+        # check the .well-known request and send a response
+        self.assertEqual(len(well_known_server.requests), 1)
+        request = well_known_server.requests[0]
+        self._send_well_known_response(request, content, headers=response_headers)
+        return well_known_server
+
+    def _send_well_known_response(self, request, content, headers={}):
+        """Check that an incoming request looks like a valid .well-known request, and
+        send back the response.
+        """
+        self.assertEqual(request.method, b'GET')
+        self.assertEqual(request.path, b'/.well-known/matrix/server')
+        self.assertEqual(
+            request.requestHeaders.getRawHeaders(b'host'),
+            [b'testserv'],
+        )
+        # send back a response
+        for k, v in headers.items():
+            request.setHeader(k, v)
+        request.write(content)
+        request.finish()
+
+        self.reactor.pump((0.1, ))
+
+    def test_get(self):
+        """
+        happy-path test of a GET request with an explicit port
+        """
+        self.reactor.lookups["testserv"] = "1.2.3.4"
+        test_d = self._make_get_request(b"matrix://testserv:8448/foo/bar")
+
+        # Nothing happened yet
+        self.assertNoResult(test_d)
+
+        # Make sure treq is trying to connect
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, client_factory, _timeout, _bindAddress) = clients[0]
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 8448)
+
+        # make a test server, and wire up the client
+        http_server = self._make_connection(
+            client_factory,
+            expected_sni=b"testserv",
+        )
+
+        self.assertEqual(len(http_server.requests), 1)
+        request = http_server.requests[0]
+        self.assertEqual(request.method, b'GET')
+        self.assertEqual(request.path, b'/foo/bar')
+        self.assertEqual(
+            request.requestHeaders.getRawHeaders(b'host'),
+            [b'testserv:8448']
+        )
+        content = request.content.read()
+        self.assertEqual(content, b'')
+
+        # Deferred is still without a result
+        self.assertNoResult(test_d)
+
+        # send the headers
+        request.responseHeaders.setRawHeaders(b'Content-Type', [b'application/json'])
+        request.write('')
+
+        self.reactor.pump((0.1,))
+
+        response = self.successResultOf(test_d)
+
+        # that should give us a Response object
+        self.assertEqual(response.code, 200)
+
+        # Send the body
+        request.write('{ "a": 1 }'.encode('ascii'))
+        request.finish()
+
+        self.reactor.pump((0.1,))
+
+        # check it can be read
+        json = self.successResultOf(treq.json_content(response))
+        self.assertEqual(json, {"a": 1})
+
+    def test_get_ip_address(self):
+        """
+        Test the behaviour when the server name contains an explicit IP (with no port)
+        """
+        # there will be a getaddrinfo on the IP
+        self.reactor.lookups["1.2.3.4"] = "1.2.3.4"
+
+        test_d = self._make_get_request(b"matrix://1.2.3.4/foo/bar")
+
+        # Nothing happened yet
+        self.assertNoResult(test_d)
+
+        # Make sure treq is trying to connect
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, client_factory, _timeout, _bindAddress) = clients[0]
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 8448)
+
+        # make a test server, and wire up the client
+        http_server = self._make_connection(
+            client_factory,
+            expected_sni=None,
+        )
+
+        self.assertEqual(len(http_server.requests), 1)
+        request = http_server.requests[0]
+        self.assertEqual(request.method, b'GET')
+        self.assertEqual(request.path, b'/foo/bar')
+        self.assertEqual(
+            request.requestHeaders.getRawHeaders(b'host'),
+            [b'1.2.3.4'],
+        )
+
+        # finish the request
+        request.finish()
+        self.reactor.pump((0.1,))
+        self.successResultOf(test_d)
+
+    def test_get_ipv6_address(self):
+        """
+        Test the behaviour when the server name contains an explicit IPv6 address
+        (with no port)
+        """
+
+        # there will be a getaddrinfo on the IP
+        self.reactor.lookups["::1"] = "::1"
+
+        test_d = self._make_get_request(b"matrix://[::1]/foo/bar")
+
+        # Nothing happened yet
+        self.assertNoResult(test_d)
+
+        # Make sure treq is trying to connect
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, client_factory, _timeout, _bindAddress) = clients[0]
+        self.assertEqual(host, '::1')
+        self.assertEqual(port, 8448)
+
+        # make a test server, and wire up the client
+        http_server = self._make_connection(
+            client_factory,
+            expected_sni=None,
+        )
+
+        self.assertEqual(len(http_server.requests), 1)
+        request = http_server.requests[0]
+        self.assertEqual(request.method, b'GET')
+        self.assertEqual(request.path, b'/foo/bar')
+        self.assertEqual(
+            request.requestHeaders.getRawHeaders(b'host'),
+            [b'[::1]'],
+        )
+
+        # finish the request
+        request.finish()
+        self.reactor.pump((0.1,))
+        self.successResultOf(test_d)
+
+    def test_get_ipv6_address_with_port(self):
+        """
+        Test the behaviour when the server name contains an explicit IPv6 address
+        (with explicit port)
+        """
+
+        # there will be a getaddrinfo on the IP
+        self.reactor.lookups["::1"] = "::1"
+
+        test_d = self._make_get_request(b"matrix://[::1]:80/foo/bar")
+
+        # Nothing happened yet
+        self.assertNoResult(test_d)
+
+        # Make sure treq is trying to connect
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, client_factory, _timeout, _bindAddress) = clients[0]
+        self.assertEqual(host, '::1')
+        self.assertEqual(port, 80)
+
+        # make a test server, and wire up the client
+        http_server = self._make_connection(
+            client_factory,
+            expected_sni=None,
+        )
+
+        self.assertEqual(len(http_server.requests), 1)
+        request = http_server.requests[0]
+        self.assertEqual(request.method, b'GET')
+        self.assertEqual(request.path, b'/foo/bar')
+        self.assertEqual(
+            request.requestHeaders.getRawHeaders(b'host'),
+            [b'[::1]:80'],
+        )
+
+        # finish the request
+        request.finish()
+        self.reactor.pump((0.1,))
+        self.successResultOf(test_d)
+
+    def test_get_no_srv_no_well_known(self):
+        """
+        Test the behaviour when the server name has no port, no SRV, and no well-known
+        """
+
+        self.mock_resolver.resolve_service.side_effect = lambda _: []
+        self.reactor.lookups["testserv"] = "1.2.3.4"
+
+        test_d = self._make_get_request(b"matrix://testserv/foo/bar")
+
+        # Nothing happened yet
+        self.assertNoResult(test_d)
+
+        # No SRV record lookup yet
+        self.mock_resolver.resolve_service.assert_not_called()
+
+        # there should be an attempt to connect on port 443 for the .well-known
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, client_factory, _timeout, _bindAddress) = clients[0]
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 443)
+
+        # fonx the connection
+        client_factory.clientConnectionFailed(None, Exception("nope"))
+
+        # attemptdelay on the hostnameendpoint is 0.3, so  takes that long before the
+        # .well-known request fails.
+        self.reactor.pump((0.4,))
+
+        # now there should be a SRV lookup
+        self.mock_resolver.resolve_service.assert_called_once_with(
+            b"_matrix._tcp.testserv",
+        )
+
+        # we should fall back to a direct connection
+        self.assertEqual(len(clients), 2)
+        (host, port, client_factory, _timeout, _bindAddress) = clients[1]
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 8448)
+
+        # make a test server, and wire up the client
+        http_server = self._make_connection(
+            client_factory,
+            expected_sni=b'testserv',
+        )
+
+        self.assertEqual(len(http_server.requests), 1)
+        request = http_server.requests[0]
+        self.assertEqual(request.method, b'GET')
+        self.assertEqual(request.path, b'/foo/bar')
+        self.assertEqual(
+            request.requestHeaders.getRawHeaders(b'host'),
+            [b'testserv'],
+        )
+
+        # finish the request
+        request.finish()
+        self.reactor.pump((0.1,))
+        self.successResultOf(test_d)
+
+    def test_get_well_known(self):
+        """Test the behaviour when the .well-known delegates elsewhere
+        """
+
+        self.mock_resolver.resolve_service.side_effect = lambda _: []
+        self.reactor.lookups["testserv"] = "1.2.3.4"
+        self.reactor.lookups["target-server"] = "1::f"
+
+        test_d = self._make_get_request(b"matrix://testserv/foo/bar")
+
+        # Nothing happened yet
+        self.assertNoResult(test_d)
+
+        # there should be an attempt to connect on port 443 for the .well-known
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, client_factory, _timeout, _bindAddress) = clients[0]
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 443)
+
+        self._handle_well_known_connection(
+            client_factory, expected_sni=b"testserv",
+            content=b'{ "m.server": "target-server" }',
+        )
+
+        # there should be a SRV lookup
+        self.mock_resolver.resolve_service.assert_called_once_with(
+            b"_matrix._tcp.target-server",
+        )
+
+        # now we should get a connection to the target server
+        self.assertEqual(len(clients), 2)
+        (host, port, client_factory, _timeout, _bindAddress) = clients[1]
+        self.assertEqual(host, '1::f')
+        self.assertEqual(port, 8448)
+
+        # make a test server, and wire up the client
+        http_server = self._make_connection(
+            client_factory,
+            expected_sni=b'target-server',
+        )
+
+        self.assertEqual(len(http_server.requests), 1)
+        request = http_server.requests[0]
+        self.assertEqual(request.method, b'GET')
+        self.assertEqual(request.path, b'/foo/bar')
+        self.assertEqual(
+            request.requestHeaders.getRawHeaders(b'host'),
+            [b'target-server'],
+        )
+
+        # finish the request
+        request.finish()
+        self.reactor.pump((0.1,))
+        self.successResultOf(test_d)
+
+        self.assertEqual(self.well_known_cache[b"testserv"], b"target-server")
+
+        # check the cache expires
+        self.reactor.pump((25 * 3600,))
+        self.well_known_cache.expire()
+        self.assertNotIn(b"testserv", self.well_known_cache)
+
+    def test_get_well_known_redirect(self):
+        """Test the behaviour when the server name has no port and no SRV record, but
+        the .well-known has a 300 redirect
+        """
+        self.mock_resolver.resolve_service.side_effect = lambda _: []
+        self.reactor.lookups["testserv"] = "1.2.3.4"
+        self.reactor.lookups["target-server"] = "1::f"
+
+        test_d = self._make_get_request(b"matrix://testserv/foo/bar")
+
+        # Nothing happened yet
+        self.assertNoResult(test_d)
+
+        # there should be an attempt to connect on port 443 for the .well-known
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, client_factory, _timeout, _bindAddress) = clients.pop()
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 443)
+
+        redirect_server = self._make_connection(
+            client_factory,
+            expected_sni=b"testserv",
+        )
+
+        # send a 302 redirect
+        self.assertEqual(len(redirect_server.requests), 1)
+        request = redirect_server.requests[0]
+        request.redirect(b'https://testserv/even_better_known')
+        request.finish()
+
+        self.reactor.pump((0.1, ))
+
+        # now there should be another connection
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, client_factory, _timeout, _bindAddress) = clients.pop()
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 443)
+
+        well_known_server = self._make_connection(
+            client_factory,
+            expected_sni=b"testserv",
+        )
+
+        self.assertEqual(len(well_known_server.requests), 1, "No request after 302")
+        request = well_known_server.requests[0]
+        self.assertEqual(request.method, b'GET')
+        self.assertEqual(request.path, b'/even_better_known')
+        request.write(b'{ "m.server": "target-server" }')
+        request.finish()
+
+        self.reactor.pump((0.1, ))
+
+        # there should be a SRV lookup
+        self.mock_resolver.resolve_service.assert_called_once_with(
+            b"_matrix._tcp.target-server",
+        )
+
+        # now we should get a connection to the target server
+        self.assertEqual(len(clients), 1)
+        (host, port, client_factory, _timeout, _bindAddress) = clients[0]
+        self.assertEqual(host, '1::f')
+        self.assertEqual(port, 8448)
+
+        # make a test server, and wire up the client
+        http_server = self._make_connection(
+            client_factory,
+            expected_sni=b'target-server',
+        )
+
+        self.assertEqual(len(http_server.requests), 1)
+        request = http_server.requests[0]
+        self.assertEqual(request.method, b'GET')
+        self.assertEqual(request.path, b'/foo/bar')
+        self.assertEqual(
+            request.requestHeaders.getRawHeaders(b'host'),
+            [b'target-server'],
+        )
+
+        # finish the request
+        request.finish()
+        self.reactor.pump((0.1,))
+        self.successResultOf(test_d)
+
+        self.assertEqual(self.well_known_cache[b"testserv"], b"target-server")
+
+        # check the cache expires
+        self.reactor.pump((25 * 3600,))
+        self.well_known_cache.expire()
+        self.assertNotIn(b"testserv", self.well_known_cache)
+
+    def test_get_invalid_well_known(self):
+        """
+        Test the behaviour when the server name has an *invalid* well-known (and no SRV)
+        """
+
+        self.mock_resolver.resolve_service.side_effect = lambda _: []
+        self.reactor.lookups["testserv"] = "1.2.3.4"
+
+        test_d = self._make_get_request(b"matrix://testserv/foo/bar")
+
+        # Nothing happened yet
+        self.assertNoResult(test_d)
+
+        # No SRV record lookup yet
+        self.mock_resolver.resolve_service.assert_not_called()
+
+        # there should be an attempt to connect on port 443 for the .well-known
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, client_factory, _timeout, _bindAddress) = clients.pop()
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 443)
+
+        self._handle_well_known_connection(
+            client_factory, expected_sni=b"testserv", content=b'NOT JSON',
+        )
+
+        # now there should be a SRV lookup
+        self.mock_resolver.resolve_service.assert_called_once_with(
+            b"_matrix._tcp.testserv",
+        )
+
+        # we should fall back to a direct connection
+        self.assertEqual(len(clients), 1)
+        (host, port, client_factory, _timeout, _bindAddress) = clients.pop()
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 8448)
+
+        # make a test server, and wire up the client
+        http_server = self._make_connection(
+            client_factory,
+            expected_sni=b'testserv',
+        )
+
+        self.assertEqual(len(http_server.requests), 1)
+        request = http_server.requests[0]
+        self.assertEqual(request.method, b'GET')
+        self.assertEqual(request.path, b'/foo/bar')
+        self.assertEqual(
+            request.requestHeaders.getRawHeaders(b'host'),
+            [b'testserv'],
+        )
+
+        # finish the request
+        request.finish()
+        self.reactor.pump((0.1,))
+        self.successResultOf(test_d)
+
+    def test_get_hostname_srv(self):
+        """
+        Test the behaviour when there is a single SRV record
+        """
+        self.mock_resolver.resolve_service.side_effect = lambda _: [
+            Server(host=b"srvtarget", port=8443)
+        ]
+        self.reactor.lookups["srvtarget"] = "1.2.3.4"
+
+        test_d = self._make_get_request(b"matrix://testserv/foo/bar")
+
+        # Nothing happened yet
+        self.assertNoResult(test_d)
+
+        # the request for a .well-known will have failed with a DNS lookup error.
+        self.mock_resolver.resolve_service.assert_called_once_with(
+            b"_matrix._tcp.testserv",
+        )
+
+        # Make sure treq is trying to connect
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, client_factory, _timeout, _bindAddress) = clients[0]
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 8443)
+
+        # make a test server, and wire up the client
+        http_server = self._make_connection(
+            client_factory,
+            expected_sni=b'testserv',
+        )
+
+        self.assertEqual(len(http_server.requests), 1)
+        request = http_server.requests[0]
+        self.assertEqual(request.method, b'GET')
+        self.assertEqual(request.path, b'/foo/bar')
+        self.assertEqual(
+            request.requestHeaders.getRawHeaders(b'host'),
+            [b'testserv'],
+        )
+
+        # finish the request
+        request.finish()
+        self.reactor.pump((0.1,))
+        self.successResultOf(test_d)
+
+    def test_get_well_known_srv(self):
+        """Test the behaviour when the .well-known redirects to a place where there
+        is a SRV.
+        """
+        self.reactor.lookups["testserv"] = "1.2.3.4"
+        self.reactor.lookups["srvtarget"] = "5.6.7.8"
+
+        test_d = self._make_get_request(b"matrix://testserv/foo/bar")
+
+        # Nothing happened yet
+        self.assertNoResult(test_d)
+
+        # there should be an attempt to connect on port 443 for the .well-known
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, client_factory, _timeout, _bindAddress) = clients[0]
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 443)
+
+        self.mock_resolver.resolve_service.side_effect = lambda _: [
+            Server(host=b"srvtarget", port=8443),
+        ]
+
+        self._handle_well_known_connection(
+            client_factory, expected_sni=b"testserv",
+            content=b'{ "m.server": "target-server" }',
+        )
+
+        # there should be a SRV lookup
+        self.mock_resolver.resolve_service.assert_called_once_with(
+            b"_matrix._tcp.target-server",
+        )
+
+        # now we should get a connection to the target of the SRV record
+        self.assertEqual(len(clients), 2)
+        (host, port, client_factory, _timeout, _bindAddress) = clients[1]
+        self.assertEqual(host, '5.6.7.8')
+        self.assertEqual(port, 8443)
+
+        # make a test server, and wire up the client
+        http_server = self._make_connection(
+            client_factory,
+            expected_sni=b'target-server',
+        )
+
+        self.assertEqual(len(http_server.requests), 1)
+        request = http_server.requests[0]
+        self.assertEqual(request.method, b'GET')
+        self.assertEqual(request.path, b'/foo/bar')
+        self.assertEqual(
+            request.requestHeaders.getRawHeaders(b'host'),
+            [b'target-server'],
+        )
+
+        # finish the request
+        request.finish()
+        self.reactor.pump((0.1,))
+        self.successResultOf(test_d)
+
+    def test_idna_servername(self):
+        """test the behaviour when the server name has idna chars in"""
+
+        self.mock_resolver.resolve_service.side_effect = lambda _: []
+
+        # the resolver is always called with the IDNA hostname as a native string.
+        self.reactor.lookups["xn--bcher-kva.com"] = "1.2.3.4"
+
+        # this is idna for bücher.com
+        test_d = self._make_get_request(b"matrix://xn--bcher-kva.com/foo/bar")
+
+        # Nothing happened yet
+        self.assertNoResult(test_d)
+
+        # No SRV record lookup yet
+        self.mock_resolver.resolve_service.assert_not_called()
+
+        # there should be an attempt to connect on port 443 for the .well-known
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, client_factory, _timeout, _bindAddress) = clients[0]
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 443)
+
+        # fonx the connection
+        client_factory.clientConnectionFailed(None, Exception("nope"))
+
+        # attemptdelay on the hostnameendpoint is 0.3, so  takes that long before the
+        # .well-known request fails.
+        self.reactor.pump((0.4,))
+
+        # now there should have been a SRV lookup
+        self.mock_resolver.resolve_service.assert_called_once_with(
+            b"_matrix._tcp.xn--bcher-kva.com",
+        )
+
+        # We should fall back to port 8448
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 2)
+        (host, port, client_factory, _timeout, _bindAddress) = clients[1]
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 8448)
+
+        # make a test server, and wire up the client
+        http_server = self._make_connection(
+            client_factory,
+            expected_sni=b'xn--bcher-kva.com',
+        )
+
+        self.assertEqual(len(http_server.requests), 1)
+        request = http_server.requests[0]
+        self.assertEqual(request.method, b'GET')
+        self.assertEqual(request.path, b'/foo/bar')
+        self.assertEqual(
+            request.requestHeaders.getRawHeaders(b'host'),
+            [b'xn--bcher-kva.com'],
+        )
+
+        # finish the request
+        request.finish()
+        self.reactor.pump((0.1,))
+        self.successResultOf(test_d)
+
+    def test_idna_srv_target(self):
+        """test the behaviour when the target of a SRV record has idna chars"""
+
+        self.mock_resolver.resolve_service.side_effect = lambda _: [
+            Server(host=b"xn--trget-3qa.com", port=8443)  # târget.com
+        ]
+        self.reactor.lookups["xn--trget-3qa.com"] = "1.2.3.4"
+
+        test_d = self._make_get_request(b"matrix://xn--bcher-kva.com/foo/bar")
+
+        # Nothing happened yet
+        self.assertNoResult(test_d)
+
+        self.mock_resolver.resolve_service.assert_called_once_with(
+            b"_matrix._tcp.xn--bcher-kva.com",
+        )
+
+        # Make sure treq is trying to connect
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, client_factory, _timeout, _bindAddress) = clients[0]
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 8443)
+
+        # make a test server, and wire up the client
+        http_server = self._make_connection(
+            client_factory,
+            expected_sni=b'xn--bcher-kva.com',
+        )
+
+        self.assertEqual(len(http_server.requests), 1)
+        request = http_server.requests[0]
+        self.assertEqual(request.method, b'GET')
+        self.assertEqual(request.path, b'/foo/bar')
+        self.assertEqual(
+            request.requestHeaders.getRawHeaders(b'host'),
+            [b'xn--bcher-kva.com'],
+        )
+
+        # finish the request
+        request.finish()
+        self.reactor.pump((0.1,))
+        self.successResultOf(test_d)
+
+    @defer.inlineCallbacks
+    def do_get_well_known(self, serv):
+        try:
+            result = yield self.agent._get_well_known(serv)
+            logger.info("Result from well-known fetch: %s", result)
+        except Exception as e:
+            logger.warning("Error fetching well-known: %s", e)
+            raise
+        defer.returnValue(result)
+
+    def test_well_known_cache(self):
+        self.reactor.lookups["testserv"] = "1.2.3.4"
+
+        fetch_d = self.do_get_well_known(b'testserv')
+
+        # there should be an attempt to connect on port 443 for the .well-known
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, client_factory, _timeout, _bindAddress) = clients.pop(0)
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 443)
+
+        well_known_server = self._handle_well_known_connection(
+            client_factory,
+            expected_sni=b"testserv",
+            response_headers={b'Cache-Control': b'max-age=10'},
+            content=b'{ "m.server": "target-server" }',
+        )
+
+        r = self.successResultOf(fetch_d)
+        self.assertEqual(r, b'target-server')
+
+        # close the tcp connection
+        well_known_server.loseConnection()
+
+        # repeat the request: it should hit the cache
+        fetch_d = self.do_get_well_known(b'testserv')
+        r = self.successResultOf(fetch_d)
+        self.assertEqual(r, b'target-server')
+
+        # expire the cache
+        self.reactor.pump((10.0,))
+
+        # now it should connect again
+        fetch_d = self.do_get_well_known(b'testserv')
+
+        self.assertEqual(len(clients), 1)
+        (host, port, client_factory, _timeout, _bindAddress) = clients.pop(0)
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 443)
+
+        self._handle_well_known_connection(
+            client_factory,
+            expected_sni=b"testserv",
+            content=b'{ "m.server": "other-server" }',
+        )
+
+        r = self.successResultOf(fetch_d)
+        self.assertEqual(r, b'other-server')
+
+
+class TestCachePeriodFromHeaders(TestCase):
+    def test_cache_control(self):
+        # uppercase
+        self.assertEqual(
+            _cache_period_from_headers(
+                Headers({b'Cache-Control': [b'foo, Max-Age = 100, bar']}),
+            ), 100,
+        )
+
+        # missing value
+        self.assertIsNone(_cache_period_from_headers(
+            Headers({b'Cache-Control': [b'max-age=, bar']}),
+        ))
+
+        # hackernews: bogus due to semicolon
+        self.assertIsNone(_cache_period_from_headers(
+            Headers({b'Cache-Control': [b'private; max-age=0']}),
+        ))
+
+        # github
+        self.assertEqual(
+            _cache_period_from_headers(
+                Headers({b'Cache-Control': [b'max-age=0, private, must-revalidate']}),
+            ), 0,
+        )
+
+        # google
+        self.assertEqual(
+            _cache_period_from_headers(
+                Headers({b'cache-control': [b'private, max-age=0']}),
+            ), 0,
+        )
+
+    def test_expires(self):
+        self.assertEqual(
+            _cache_period_from_headers(
+                Headers({b'Expires': [b'Wed, 30 Jan 2019 07:35:33 GMT']}),
+                time_now=lambda: 1548833700
+            ), 33,
+        )
+
+        # cache-control overrides expires
+        self.assertEqual(
+            _cache_period_from_headers(
+                Headers({
+                    b'cache-control': [b'max-age=10'],
+                    b'Expires': [b'Wed, 30 Jan 2019 07:35:33 GMT']
+                }),
+                time_now=lambda: 1548833700
+            ), 10,
+        )
+
+        # invalid expires means immediate expiry
+        self.assertEqual(
+            _cache_period_from_headers(
+                Headers({b'Expires': [b'0']}),
+            ), 0,
+        )
+
+
+def _check_logcontext(context):
+    current = LoggingContext.current_context()
+    if current is not context:
+        raise AssertionError(
+            "Expected logcontext %s but was %s" % (context, current),
+        )
+
+
+def _build_test_server():
+    """Construct a test server
+
+    This builds an HTTP channel, wrapped with a TLSMemoryBIOProtocol
+
+    Returns:
+        TLSMemoryBIOProtocol
+    """
+    server_factory = Factory.forProtocol(HTTPChannel)
+    # Request.finish expects the factory to have a 'log' method.
+    server_factory.log = _log_request
+
+    server_tls_factory = TLSMemoryBIOFactory(
+        ServerTLSContext(), isClient=False, wrappedFactory=server_factory,
+    )
+
+    return server_tls_factory.buildProtocol(None)
+
+
+def _log_request(request):
+    """Implements Factory.log, which is expected by Request.finish"""
+    logger.info("Completed request %s", request)
+
+
+@implementer(IPolicyForHTTPS)
+class TrustingTLSPolicyForHTTPS(object):
+    """An IPolicyForHTTPS which doesn't do any certificate verification"""
+    def creatorForNetloc(self, hostname, port):
+        certificateOptions = OpenSSLCertificateOptions()
+        return ClientTLSOptions(hostname, certificateOptions.getContext())
diff --git a/tests/http/federation/test_srv_resolver.py b/tests/http/federation/test_srv_resolver.py
new file mode 100644
index 00000000..a872e244
--- /dev/null
+++ b/tests/http/federation/test_srv_resolver.py
@@ -0,0 +1,207 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2019 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from mock import Mock
+
+from twisted.internet import defer
+from twisted.internet.defer import Deferred
+from twisted.internet.error import ConnectError
+from twisted.names import dns, error
+
+from synapse.http.federation.srv_resolver import SrvResolver
+from synapse.util.logcontext import LoggingContext
+
+from tests import unittest
+from tests.utils import MockClock
+
+
+class SrvResolverTestCase(unittest.TestCase):
+    def test_resolve(self):
+        dns_client_mock = Mock()
+
+        service_name = b"test_service.example.com"
+        host_name = b"example.com"
+
+        answer_srv = dns.RRHeader(
+            type=dns.SRV, payload=dns.Record_SRV(target=host_name)
+        )
+
+        result_deferred = Deferred()
+        dns_client_mock.lookupService.return_value = result_deferred
+
+        cache = {}
+        resolver = SrvResolver(dns_client=dns_client_mock, cache=cache)
+
+        @defer.inlineCallbacks
+        def do_lookup():
+
+            with LoggingContext("one") as ctx:
+                resolve_d = resolver.resolve_service(service_name)
+
+                self.assertNoResult(resolve_d)
+
+                # should have reset to the sentinel context
+                self.assertIs(LoggingContext.current_context(), LoggingContext.sentinel)
+
+                result = yield resolve_d
+
+                # should have restored our context
+                self.assertIs(LoggingContext.current_context(), ctx)
+
+                defer.returnValue(result)
+
+        test_d = do_lookup()
+        self.assertNoResult(test_d)
+
+        dns_client_mock.lookupService.assert_called_once_with(service_name)
+
+        result_deferred.callback(
+            ([answer_srv], None, None)
+        )
+
+        servers = self.successResultOf(test_d)
+
+        self.assertEquals(len(servers), 1)
+        self.assertEquals(servers, cache[service_name])
+        self.assertEquals(servers[0].host, host_name)
+
+    @defer.inlineCallbacks
+    def test_from_cache_expired_and_dns_fail(self):
+        dns_client_mock = Mock()
+        dns_client_mock.lookupService.return_value = defer.fail(error.DNSServerError())
+
+        service_name = b"test_service.example.com"
+
+        entry = Mock(spec_set=["expires"])
+        entry.expires = 0
+
+        cache = {service_name: [entry]}
+        resolver = SrvResolver(dns_client=dns_client_mock, cache=cache)
+
+        servers = yield resolver.resolve_service(service_name)
+
+        dns_client_mock.lookupService.assert_called_once_with(service_name)
+
+        self.assertEquals(len(servers), 1)
+        self.assertEquals(servers, cache[service_name])
+
+    @defer.inlineCallbacks
+    def test_from_cache(self):
+        clock = MockClock()
+
+        dns_client_mock = Mock(spec_set=['lookupService'])
+        dns_client_mock.lookupService = Mock(spec_set=[])
+
+        service_name = b"test_service.example.com"
+
+        entry = Mock(spec_set=["expires"])
+        entry.expires = 999999999
+
+        cache = {service_name: [entry]}
+        resolver = SrvResolver(
+            dns_client=dns_client_mock, cache=cache, get_time=clock.time,
+        )
+
+        servers = yield resolver.resolve_service(service_name)
+
+        self.assertFalse(dns_client_mock.lookupService.called)
+
+        self.assertEquals(len(servers), 1)
+        self.assertEquals(servers, cache[service_name])
+
+    @defer.inlineCallbacks
+    def test_empty_cache(self):
+        dns_client_mock = Mock()
+
+        dns_client_mock.lookupService.return_value = defer.fail(error.DNSServerError())
+
+        service_name = b"test_service.example.com"
+
+        cache = {}
+        resolver = SrvResolver(dns_client=dns_client_mock, cache=cache)
+
+        with self.assertRaises(error.DNSServerError):
+            yield resolver.resolve_service(service_name)
+
+    @defer.inlineCallbacks
+    def test_name_error(self):
+        dns_client_mock = Mock()
+
+        dns_client_mock.lookupService.return_value = defer.fail(error.DNSNameError())
+
+        service_name = b"test_service.example.com"
+
+        cache = {}
+        resolver = SrvResolver(dns_client=dns_client_mock, cache=cache)
+
+        servers = yield resolver.resolve_service(service_name)
+
+        self.assertEquals(len(servers), 0)
+        self.assertEquals(len(cache), 0)
+
+    def test_disabled_service(self):
+        """
+        test the behaviour when there is a single record which is ".".
+        """
+        service_name = b"test_service.example.com"
+
+        lookup_deferred = Deferred()
+        dns_client_mock = Mock()
+        dns_client_mock.lookupService.return_value = lookup_deferred
+        cache = {}
+        resolver = SrvResolver(dns_client=dns_client_mock, cache=cache)
+
+        resolve_d = resolver.resolve_service(service_name)
+        self.assertNoResult(resolve_d)
+
+        # returning a single "." should make the lookup fail with a ConenctError
+        lookup_deferred.callback((
+            [dns.RRHeader(type=dns.SRV, payload=dns.Record_SRV(target=b"."))],
+            None,
+            None,
+        ))
+
+        self.failureResultOf(resolve_d, ConnectError)
+
+    def test_non_srv_answer(self):
+        """
+        test the behaviour when the dns server gives us a spurious non-SRV response
+        """
+        service_name = b"test_service.example.com"
+
+        lookup_deferred = Deferred()
+        dns_client_mock = Mock()
+        dns_client_mock.lookupService.return_value = lookup_deferred
+        cache = {}
+        resolver = SrvResolver(dns_client=dns_client_mock, cache=cache)
+
+        resolve_d = resolver.resolve_service(service_name)
+        self.assertNoResult(resolve_d)
+
+        lookup_deferred.callback((
+            [
+                dns.RRHeader(type=dns.A, payload=dns.Record_A()),
+                dns.RRHeader(type=dns.SRV, payload=dns.Record_SRV(target=b"host")),
+            ],
+            None,
+            None,
+        ))
+
+        servers = self.successResultOf(resolve_d)
+
+        self.assertEquals(len(servers), 1)
+        self.assertEquals(servers, cache[service_name])
+        self.assertEquals(servers[0].host, b"host")
diff --git a/tests/http/server.pem b/tests/http/server.pem
new file mode 100644
index 00000000..0584cf1a
--- /dev/null
+++ b/tests/http/server.pem
@@ -0,0 +1,81 @@
+-----BEGIN PRIVATE KEY-----
+MIIJQgIBADANBgkqhkiG9w0BAQEFAASCCSwwggkoAgEAAoICAQCgF43/3lAgJ+p0
+x7Rn8UcL8a4fctvdkikvZrCngw96LkB34Evfq8YGWlOVjU+f9naUJLAKMatmAfEN
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+gwtbrKM2Alyg4wyA2hTlWOH/CAzH0RlCJ9Fs/d1/xJVJBeuyajLiB3/6vXTS6qnq
+I7BSSxAPG8eGcn21LSsjNeB7ZZtaTgNnu/8ZBUYo9yrgkWc67TZe3/ChldYxOOlO
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+/0TilzCaJ/9K9pKNhaClVRy7Dt8QjYg6BIWCGSw4ApF7pLnQ9gySn95mersCkVzD
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+KILVFsq3cQC+bEnoM4eVbjEQkGs1RQ==
+-----END PRIVATE KEY-----
+-----BEGIN CERTIFICATE-----
+MIIE/jCCAuagAwIBAgIJANFtVaGvJWZlMA0GCSqGSIb3DQEBCwUAMBMxETAPBgNV
+BAMMCHRlc3RzZXJ2MCAXDTE5MDEyNzIyMDIzNloYDzIxMTkwMTAzMjIwMjM2WjAT
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+H3BjgyXLl+ao5/pOUYYtzm3ruTXTgRcy5hhL6hVTYhSrf9vYh4LNIeXNKnZ78tyG
+TX77/kU2qXhBGCFEUUMqUNV/+ITir2lmoxVjknt19M07aGr8C7SgYt6Rs+qDpMiy
+JurgvRh8LpVq4pHx1efxzxCFmo58DMrG40I0+CF3y/niNpOb1gp2wAqByRiORkds
+f0ytW6qZ0TpHbD6gOtQLYDnhx3ISuX+QYSekVwQUpffeWQ==
+-----END CERTIFICATE-----
diff --git a/tests/http/test_fedclient.py b/tests/http/test_fedclient.py
index b2e38276..018c77eb 100644
--- a/tests/http/test_fedclient.py
+++ b/tests/http/test_fedclient.py
@@ -15,8 +15,10 @@
 
 from mock import Mock
 
+from twisted.internet import defer
 from twisted.internet.defer import TimeoutError
 from twisted.internet.error import ConnectingCancelledError, DNSLookupError
+from twisted.test.proto_helpers import StringTransport
 from twisted.web.client import ResponseNeverReceived
 from twisted.web.http import HTTPChannel
 
@@ -25,11 +27,20 @@ from synapse.http.matrixfederationclient import (
     MatrixFederationHttpClient,
     MatrixFederationRequest,
 )
+from synapse.util.logcontext import LoggingContext
 
 from tests.server import FakeTransport
 from tests.unittest import HomeserverTestCase
 
 
+def check_logcontext(context):
+    current = LoggingContext.current_context()
+    if current is not context:
+        raise AssertionError(
+            "Expected logcontext %s but was %s" % (context, current),
+        )
+
+
 class FederationClientTests(HomeserverTestCase):
     def make_homeserver(self, reactor, clock):
 
@@ -38,13 +49,77 @@ class FederationClientTests(HomeserverTestCase):
         return hs
 
     def prepare(self, reactor, clock, homeserver):
-
         self.cl = MatrixFederationHttpClient(self.hs)
         self.reactor.lookups["testserv"] = "1.2.3.4"
 
+    def test_client_get(self):
+        """
+        happy-path test of a GET request
+        """
+        @defer.inlineCallbacks
+        def do_request():
+            with LoggingContext("one") as context:
+                fetch_d = self.cl.get_json("testserv:8008", "foo/bar")
+
+                # Nothing happened yet
+                self.assertNoResult(fetch_d)
+
+                # should have reset logcontext to the sentinel
+                check_logcontext(LoggingContext.sentinel)
+
+                try:
+                    fetch_res = yield fetch_d
+                    defer.returnValue(fetch_res)
+                finally:
+                    check_logcontext(context)
+
+        test_d = do_request()
+
+        self.pump()
+
+        # Nothing happened yet
+        self.assertNoResult(test_d)
+
+        # Make sure treq is trying to connect
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, factory, _timeout, _bindAddress) = clients[0]
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 8008)
+
+        # complete the connection and wire it up to a fake transport
+        protocol = factory.buildProtocol(None)
+        transport = StringTransport()
+        protocol.makeConnection(transport)
+
+        # that should have made it send the request to the transport
+        self.assertRegex(transport.value(), b"^GET /foo/bar")
+        self.assertRegex(transport.value(), b"Host: testserv:8008")
+
+        # Deferred is still without a result
+        self.assertNoResult(test_d)
+
+        # Send it the HTTP response
+        res_json = '{ "a": 1 }'.encode('ascii')
+        protocol.dataReceived(
+            b"HTTP/1.1 200 OK\r\n"
+            b"Server: Fake\r\n"
+            b"Content-Type: application/json\r\n"
+            b"Content-Length: %i\r\n"
+            b"\r\n"
+            b"%s" % (len(res_json), res_json)
+        )
+
+        self.pump()
+
+        res = self.successResultOf(test_d)
+
+        # check the response is as expected
+        self.assertEqual(res, {"a": 1})
+
     def test_dns_error(self):
         """
-        If the DNS raising returns an error, it will bubble up.
+        If the DNS lookup returns an error, it will bubble up.
         """
         d = self.cl.get_json("testserv2:8008", "foo/bar", timeout=10000)
         self.pump()
@@ -53,6 +128,28 @@ class FederationClientTests(HomeserverTestCase):
         self.assertIsInstance(f.value, RequestSendFailed)
         self.assertIsInstance(f.value.inner_exception, DNSLookupError)
 
+    def test_client_connection_refused(self):
+        d = self.cl.get_json("testserv:8008", "foo/bar", timeout=10000)
+
+        self.pump()
+
+        # Nothing happened yet
+        self.assertNoResult(d)
+
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (host, port, factory, _timeout, _bindAddress) = clients[0]
+        self.assertEqual(host, '1.2.3.4')
+        self.assertEqual(port, 8008)
+        e = Exception("go away")
+        factory.clientConnectionFailed(None, e)
+        self.pump(0.5)
+
+        f = self.failureResultOf(d)
+
+        self.assertIsInstance(f.value, RequestSendFailed)
+        self.assertIs(f.value.inner_exception, e)
+
     def test_client_never_connect(self):
         """
         If the HTTP request is not connected and is timed out, it'll give a
@@ -63,7 +160,7 @@ class FederationClientTests(HomeserverTestCase):
         self.pump()
 
         # Nothing happened yet
-        self.assertFalse(d.called)
+        self.assertNoResult(d)
 
         # Make sure treq is trying to connect
         clients = self.reactor.tcpClients
@@ -72,7 +169,7 @@ class FederationClientTests(HomeserverTestCase):
         self.assertEqual(clients[0][1], 8008)
 
         # Deferred is still without a result
-        self.assertFalse(d.called)
+        self.assertNoResult(d)
 
         # Push by enough to time it out
         self.reactor.advance(10.5)
@@ -94,7 +191,7 @@ class FederationClientTests(HomeserverTestCase):
         self.pump()
 
         # Nothing happened yet
-        self.assertFalse(d.called)
+        self.assertNoResult(d)
 
         # Make sure treq is trying to connect
         clients = self.reactor.tcpClients
@@ -107,7 +204,7 @@ class FederationClientTests(HomeserverTestCase):
         client.makeConnection(conn)
 
         # Deferred is still without a result
-        self.assertFalse(d.called)
+        self.assertNoResult(d)
 
         # Push by enough to time it out
         self.reactor.advance(10.5)
@@ -135,7 +232,7 @@ class FederationClientTests(HomeserverTestCase):
         client.makeConnection(conn)
 
         # Deferred does not have a result
-        self.assertFalse(d.called)
+        self.assertNoResult(d)
 
         # Send it the HTTP response
         client.dataReceived(b"HTTP/1.1 200 OK\r\nServer: Fake\r\n\r\n")
@@ -159,7 +256,7 @@ class FederationClientTests(HomeserverTestCase):
         client.makeConnection(conn)
 
         # Deferred does not have a result
-        self.assertFalse(d.called)
+        self.assertNoResult(d)
 
         # Send it the HTTP response
         client.dataReceived(
@@ -195,3 +292,42 @@ class FederationClientTests(HomeserverTestCase):
         request = server.requests[0]
         content = request.content.read()
         self.assertEqual(content, b'{"a":"b"}')
+
+    def test_closes_connection(self):
+        """Check that the client closes unused HTTP connections"""
+        d = self.cl.get_json("testserv:8008", "foo/bar")
+
+        self.pump()
+
+        # there should have been a call to connectTCP
+        clients = self.reactor.tcpClients
+        self.assertEqual(len(clients), 1)
+        (_host, _port, factory, _timeout, _bindAddress) = clients[0]
+
+        # complete the connection and wire it up to a fake transport
+        client = factory.buildProtocol(None)
+        conn = StringTransport()
+        client.makeConnection(conn)
+
+        # that should have made it send the request to the connection
+        self.assertRegex(conn.value(), b"^GET /foo/bar")
+
+        # Send the HTTP response
+        client.dataReceived(
+            b"HTTP/1.1 200 OK\r\n"
+            b"Content-Type: application/json\r\n"
+            b"Content-Length: 2\r\n"
+            b"\r\n"
+            b"{}"
+        )
+
+        # We should get a successful response
+        r = self.successResultOf(d)
+        self.assertEqual(r, {})
+
+        self.assertFalse(conn.disconnecting)
+
+        # wait for a while
+        self.pump(120)
+
+        self.assertTrue(conn.disconnecting)
diff --git a/tests/rest/client/v2_alpha/test_capabilities.py b/tests/rest/client/v2_alpha/test_capabilities.py
new file mode 100644
index 00000000..d3d43970
--- /dev/null
+++ b/tests/rest/client/v2_alpha/test_capabilities.py
@@ -0,0 +1,78 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from synapse.api.constants import DEFAULT_ROOM_VERSION, KNOWN_ROOM_VERSIONS
+from synapse.rest.client.v1 import admin, login
+from synapse.rest.client.v2_alpha import capabilities
+
+from tests import unittest
+
+
+class CapabilitiesTestCase(unittest.HomeserverTestCase):
+
+    servlets = [
+        admin.register_servlets,
+        capabilities.register_servlets,
+        login.register_servlets,
+    ]
+
+    def make_homeserver(self, reactor, clock):
+        self.url = b"/_matrix/client/r0/capabilities"
+        hs = self.setup_test_homeserver()
+        self.store = hs.get_datastore()
+        return hs
+
+    def test_check_auth_required(self):
+        request, channel = self.make_request("GET", self.url)
+        self.render(request)
+
+        self.assertEqual(channel.code, 401)
+
+    def test_get_room_version_capabilities(self):
+        self.register_user("user", "pass")
+        access_token = self.login("user", "pass")
+
+        request, channel = self.make_request("GET", self.url, access_token=access_token)
+        self.render(request)
+        capabilities = channel.json_body['capabilities']
+
+        self.assertEqual(channel.code, 200)
+        for room_version in capabilities['m.room_versions']['available'].keys():
+            self.assertTrue(room_version in KNOWN_ROOM_VERSIONS, "" + room_version)
+        self.assertEqual(
+            DEFAULT_ROOM_VERSION, capabilities['m.room_versions']['default']
+        )
+
+    def test_get_change_password_capabilities(self):
+        localpart = "user"
+        password = "pass"
+        user = self.register_user(localpart, password)
+        access_token = self.login(user, password)
+
+        request, channel = self.make_request("GET", self.url, access_token=access_token)
+        self.render(request)
+        capabilities = channel.json_body['capabilities']
+
+        self.assertEqual(channel.code, 200)
+
+        # Test case where password is handled outside of Synapse
+        self.assertTrue(capabilities['m.change_password']['enabled'])
+        self.get_success(self.store.user_set_password_hash(user, None))
+        request, channel = self.make_request("GET", self.url, access_token=access_token)
+        self.render(request)
+        capabilities = channel.json_body['capabilities']
+
+        self.assertEqual(channel.code, 200)
+        self.assertFalse(capabilities['m.change_password']['enabled'])
diff --git a/tests/server.py b/tests/server.py
index db43fa0d..fc1e76d1 100644
--- a/tests/server.py
+++ b/tests/server.py
@@ -1,4 +1,5 @@
 import json
+import logging
 from io import BytesIO
 
 from six import text_type
@@ -7,11 +8,10 @@ import attr
 from zope.interface import implementer
 
 from twisted.internet import address, threads, udp
-from twisted.internet._resolver import HostResolution
-from twisted.internet.address import IPv4Address
-from twisted.internet.defer import Deferred
+from twisted.internet._resolver import SimpleResolverComplexifier
+from twisted.internet.defer import Deferred, fail, succeed
 from twisted.internet.error import DNSLookupError
-from twisted.internet.interfaces import IReactorPluggableNameResolver
+from twisted.internet.interfaces import IReactorPluggableNameResolver, IResolverSimple
 from twisted.python.failure import Failure
 from twisted.test.proto_helpers import MemoryReactorClock
 from twisted.web.http import unquote
@@ -22,6 +22,8 @@ from synapse.util import Clock
 
 from tests.utils import setup_test_homeserver as _sth
 
+logger = logging.getLogger(__name__)
+
 
 class TimedOutException(Exception):
     """
@@ -224,30 +226,16 @@ class ThreadedMemoryReactorClock(MemoryReactorClock):
 
     def __init__(self):
         self._udp = []
-        self.lookups = {}
-
-        class Resolver(object):
-            def resolveHostName(
-                _self,
-                resolutionReceiver,
-                hostName,
-                portNumber=0,
-                addressTypes=None,
-                transportSemantics='TCP',
-            ):
-
-                resolution = HostResolution(hostName)
-                resolutionReceiver.resolutionBegan(resolution)
-                if hostName not in self.lookups:
-                    raise DNSLookupError("OH NO")
-
-                resolutionReceiver.addressResolved(
-                    IPv4Address('TCP', self.lookups[hostName], portNumber)
-                )
-                resolutionReceiver.resolutionComplete()
-                return resolution
-
-        self.nameResolver = Resolver()
+        lookups = self.lookups = {}
+
+        @implementer(IResolverSimple)
+        class FakeResolver(object):
+            def getHostByName(self, name, timeout=None):
+                if name not in lookups:
+                    return fail(DNSLookupError("OH NO: unknown %s" % (name, )))
+                return succeed(lookups[name])
+
+        self.nameResolver = SimpleResolverComplexifier(FakeResolver())
         super(ThreadedMemoryReactorClock, self).__init__()
 
     def listenUDP(self, port, protocol, interface='', maxPacketSize=8196):
@@ -339,7 +327,7 @@ def get_clock():
     return (clock, hs_clock)
 
 
-@attr.s
+@attr.s(cmp=False)
 class FakeTransport(object):
     """
     A twisted.internet.interfaces.ITransport implementation which sends all its data
@@ -366,7 +354,13 @@ class FakeTransport(object):
     :type: twisted.internet.interfaces.IReactorTime
     """
 
+    _protocol = attr.ib(default=None)
+    """The Protocol which is producing data for this transport. Optional, but if set
+    will get called back for connectionLost() notifications etc.
+    """
+
     disconnecting = False
+    disconnected = False
     buffer = attr.ib(default=b'')
     producer = attr.ib(default=None)
 
@@ -376,11 +370,17 @@ class FakeTransport(object):
     def getHost(self):
         return None
 
-    def loseConnection(self):
-        self.disconnecting = True
+    def loseConnection(self, reason=None):
+        if not self.disconnecting:
+            logger.info("FakeTransport: loseConnection(%s)", reason)
+            self.disconnecting = True
+            if self._protocol:
+                self._protocol.connectionLost(reason)
+            self.disconnected = True
 
     def abortConnection(self):
-        self.disconnecting = True
+        logger.info("FakeTransport: abortConnection()")
+        self.loseConnection()
 
     def pauseProducing(self):
         if not self.producer:
@@ -414,14 +414,29 @@ class FakeTransport(object):
         self.buffer = self.buffer + byt
 
         def _write():
+            if not self.buffer:
+                # nothing to do. Don't write empty buffers: it upsets the
+                # TLSMemoryBIOProtocol
+                return
+
+            if self.disconnected:
+                return
+            logger.info("%s->%s: %s", self._protocol, self.other, self.buffer)
+
             if getattr(self.other, "transport") is not None:
-                self.other.dataReceived(self.buffer)
-                self.buffer = b""
+                try:
+                    self.other.dataReceived(self.buffer)
+                    self.buffer = b""
+                except Exception as e:
+                    logger.warning("Exception writing to protocol: %s", e)
                 return
 
             self._reactor.callLater(0.0, _write)
 
-        _write()
+        # always actually do the write asynchronously. Some protocols (notably the
+        # TLSMemoryBIOProtocol) get very confused if a read comes back while they are
+        # still doing a write. Doing a callLater here breaks the cycle.
+        self._reactor.callLater(0.0, _write)
 
     def writeSequence(self, seq):
         for x in seq:
diff --git a/tests/state/test_v2.py b/tests/state/test_v2.py
index 2e073a3a..9a5c8169 100644
--- a/tests/state/test_v2.py
+++ b/tests/state/test_v2.py
@@ -19,7 +19,7 @@ from six.moves import zip
 
 import attr
 
-from synapse.api.constants import EventTypes, JoinRules, Membership
+from synapse.api.constants import EventTypes, JoinRules, Membership, RoomVersions
 from synapse.event_auth import auth_types_for_event
 from synapse.events import FrozenEvent
 from synapse.state.v2 import lexicographical_topological_sort, resolve_events_with_store
@@ -539,6 +539,7 @@ class StateTestCase(unittest.TestCase):
                 state_before = dict(state_at_event[prev_events[0]])
             else:
                 state_d = resolve_events_with_store(
+                    RoomVersions.V2,
                     [state_at_event[n] for n in prev_events],
                     event_map=event_map,
                     state_res_store=TestStateResolutionStore(event_map),
@@ -685,6 +686,7 @@ class SimpleParamStateTestCase(unittest.TestCase):
         # Test that we correctly handle passing `None` as the event_map
 
         state_d = resolve_events_with_store(
+            RoomVersions.V2,
             [self.state_at_bob, self.state_at_charlie],
             event_map=None,
             state_res_store=TestStateResolutionStore(self.event_map),
diff --git a/tests/storage/test_background_update.py b/tests/storage/test_background_update.py
index 81403727..5568a607 100644
--- a/tests/storage/test_background_update.py
+++ b/tests/storage/test_background_update.py
@@ -11,7 +11,7 @@ class BackgroundUpdateTestCase(unittest.TestCase):
     def setUp(self):
         hs = yield setup_test_homeserver(
             self.addCleanup
-        )  # type: synapse.server.HomeServer
+        )
         self.store = hs.get_datastore()
         self.clock = hs.get_clock()
 
diff --git a/tests/storage/test_base.py b/tests/storage/test_base.py
index 829f47d2..f18db8c3 100644
--- a/tests/storage/test_base.py
+++ b/tests/storage/test_base.py
@@ -49,13 +49,17 @@ class SQLBaseStoreTestCase(unittest.TestCase):
         self.db_pool.runWithConnection = runWithConnection
 
         config = Mock()
+        config._disable_native_upserts = True
         config.event_cache_size = 1
         config.database_config = {"name": "sqlite3"}
+        engine = create_engine(config.database_config)
+        fake_engine = Mock(wraps=engine)
+        fake_engine.can_native_upsert = False
         hs = TestHomeServer(
             "test",
             db_pool=self.db_pool,
             config=config,
-            database_engine=create_engine(config.database_config),
+            database_engine=fake_engine,
         )
 
         self.datastore = SQLBaseStore(None, hs)
diff --git a/tests/storage/test_client_ips.py b/tests/storage/test_client_ips.py
index 4577e942..858efe49 100644
--- a/tests/storage/test_client_ips.py
+++ b/tests/storage/test_client_ips.py
@@ -62,6 +62,77 @@ class ClientIpStoreTestCase(unittest.HomeserverTestCase):
             r,
         )
 
+    def test_insert_new_client_ip_none_device_id(self):
+        """
+        An insert with a device ID of NULL will not create a new entry, but
+        update an existing entry in the user_ips table.
+        """
+        self.reactor.advance(12345678)
+
+        user_id = "@user:id"
+
+        # Add & trigger the storage loop
+        self.get_success(
+            self.store.insert_client_ip(
+                user_id, "access_token", "ip", "user_agent", None
+            )
+        )
+        self.reactor.advance(200)
+        self.pump(0)
+
+        result = self.get_success(
+            self.store._simple_select_list(
+                table="user_ips",
+                keyvalues={"user_id": user_id},
+                retcols=["access_token", "ip", "user_agent", "device_id", "last_seen"],
+                desc="get_user_ip_and_agents",
+            )
+        )
+
+        self.assertEqual(
+            result,
+            [
+                {
+                    'access_token': 'access_token',
+                    'ip': 'ip',
+                    'user_agent': 'user_agent',
+                    'device_id': None,
+                    'last_seen': 12345678000,
+                }
+            ],
+        )
+
+        # Add another & trigger the storage loop
+        self.get_success(
+            self.store.insert_client_ip(
+                user_id, "access_token", "ip", "user_agent", None
+            )
+        )
+        self.reactor.advance(10)
+        self.pump(0)
+
+        result = self.get_success(
+            self.store._simple_select_list(
+                table="user_ips",
+                keyvalues={"user_id": user_id},
+                retcols=["access_token", "ip", "user_agent", "device_id", "last_seen"],
+                desc="get_user_ip_and_agents",
+            )
+        )
+        # Only one result, has been upserted.
+        self.assertEqual(
+            result,
+            [
+                {
+                    'access_token': 'access_token',
+                    'ip': 'ip',
+                    'user_agent': 'user_agent',
+                    'device_id': None,
+                    'last_seen': 12345878000,
+                }
+            ],
+        )
+
     def test_disabled_monthly_active_user(self):
         self.hs.config.limit_usage_by_mau = False
         self.hs.config.max_mau_value = 50
diff --git a/tests/storage/test_end_to_end_keys.py b/tests/storage/test_end_to_end_keys.py
index b83f7336..11fb8c0c 100644
--- a/tests/storage/test_end_to_end_keys.py
+++ b/tests/storage/test_end_to_end_keys.py
@@ -20,9 +20,6 @@ import tests.utils
 
 
 class EndToEndKeyStoreTestCase(tests.unittest.TestCase):
-    def __init__(self, *args, **kwargs):
-        super(EndToEndKeyStoreTestCase, self).__init__(*args, **kwargs)
-        self.store = None  # type: synapse.storage.DataStore
 
     @defer.inlineCallbacks
     def setUp(self):
diff --git a/tests/storage/test_keys.py b/tests/storage/test_keys.py
index 47f4a8ce..0d2dc9f3 100644
--- a/tests/storage/test_keys.py
+++ b/tests/storage/test_keys.py
@@ -22,9 +22,6 @@ import tests.utils
 
 
 class KeyStoreTestCase(tests.unittest.TestCase):
-    def __init__(self, *args, **kwargs):
-        super(KeyStoreTestCase, self).__init__(*args, **kwargs)
-        self.store = None  # type: synapse.storage.keys.KeyStore
 
     @defer.inlineCallbacks
     def setUp(self):
diff --git a/tests/storage/test_monthly_active_users.py b/tests/storage/test_monthly_active_users.py
index 9605301b..d6569a82 100644
--- a/tests/storage/test_monthly_active_users.py
+++ b/tests/storage/test_monthly_active_users.py
@@ -18,12 +18,12 @@ from twisted.internet import defer
 
 from synapse.api.constants import UserTypes
 
-from tests.unittest import HomeserverTestCase
+from tests import unittest
 
 FORTY_DAYS = 40 * 24 * 60 * 60
 
 
-class MonthlyActiveUsersTestCase(HomeserverTestCase):
+class MonthlyActiveUsersTestCase(unittest.HomeserverTestCase):
     def make_homeserver(self, reactor, clock):
 
         hs = self.setup_test_homeserver()
diff --git a/tests/storage/test_redaction.py b/tests/storage/test_redaction.py
index 02bf975f..3957561b 100644
--- a/tests/storage/test_redaction.py
+++ b/tests/storage/test_redaction.py
@@ -18,7 +18,7 @@ from mock import Mock
 
 from twisted.internet import defer
 
-from synapse.api.constants import EventTypes, Membership
+from synapse.api.constants import EventTypes, Membership, RoomVersions
 from synapse.types import RoomID, UserID
 
 from tests import unittest
@@ -52,6 +52,7 @@ class RedactionTestCase(unittest.TestCase):
         content = {"membership": membership}
         content.update(extra_content)
         builder = self.event_builder_factory.new(
+            RoomVersions.V1,
             {
                 "type": EventTypes.Member,
                 "sender": user.to_string(),
@@ -74,6 +75,7 @@ class RedactionTestCase(unittest.TestCase):
         self.depth += 1
 
         builder = self.event_builder_factory.new(
+            RoomVersions.V1,
             {
                 "type": EventTypes.Message,
                 "sender": user.to_string(),
@@ -94,6 +96,7 @@ class RedactionTestCase(unittest.TestCase):
     @defer.inlineCallbacks
     def inject_redaction(self, room, event_id, user, reason):
         builder = self.event_builder_factory.new(
+            RoomVersions.V1,
             {
                 "type": EventTypes.Redaction,
                 "sender": user.to_string(),
diff --git a/tests/storage/test_roommember.py b/tests/storage/test_roommember.py
index 978c6613..7fa2f4fd 100644
--- a/tests/storage/test_roommember.py
+++ b/tests/storage/test_roommember.py
@@ -18,7 +18,7 @@ from mock import Mock
 
 from twisted.internet import defer
 
-from synapse.api.constants import EventTypes, Membership
+from synapse.api.constants import EventTypes, Membership, RoomVersions
 from synapse.types import RoomID, UserID
 
 from tests import unittest
@@ -50,6 +50,7 @@ class RoomMemberStoreTestCase(unittest.TestCase):
     @defer.inlineCallbacks
     def inject_room_member(self, room, user, membership, replaces_state=None):
         builder = self.event_builder_factory.new(
+            RoomVersions.V1,
             {
                 "type": EventTypes.Member,
                 "sender": user.to_string(),
diff --git a/tests/storage/test_state.py b/tests/storage/test_state.py
index 086a39d8..99cd3e09 100644
--- a/tests/storage/test_state.py
+++ b/tests/storage/test_state.py
@@ -17,7 +17,7 @@ import logging
 
 from twisted.internet import defer
 
-from synapse.api.constants import EventTypes, Membership
+from synapse.api.constants import EventTypes, Membership, RoomVersions
 from synapse.storage.state import StateFilter
 from synapse.types import RoomID, UserID
 
@@ -28,9 +28,6 @@ logger = logging.getLogger(__name__)
 
 
 class StateStoreTestCase(tests.unittest.TestCase):
-    def __init__(self, *args, **kwargs):
-        super(StateStoreTestCase, self).__init__(*args, **kwargs)
-        self.store = None  # type: synapse.storage.DataStore
 
     @defer.inlineCallbacks
     def setUp(self):
@@ -52,6 +49,7 @@ class StateStoreTestCase(tests.unittest.TestCase):
     @defer.inlineCallbacks
     def inject_state_event(self, room, sender, typ, state_key, content):
         builder = self.event_builder_factory.new(
+            RoomVersions.V1,
             {
                 "type": typ,
                 "sender": sender.to_string(),
diff --git a/tests/test_dns.py b/tests/test_dns.py
deleted file mode 100644
index 90bd34be..00000000
--- a/tests/test_dns.py
+++ /dev/null
@@ -1,129 +0,0 @@
-# -*- coding: utf-8 -*-
-# Copyright 2014-2016 OpenMarket Ltd
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-from mock import Mock
-
-from twisted.internet import defer
-from twisted.names import dns, error
-
-from synapse.http.endpoint import resolve_service
-
-from tests.utils import MockClock
-
-from . import unittest
-
-
-@unittest.DEBUG
-class DnsTestCase(unittest.TestCase):
-    @defer.inlineCallbacks
-    def test_resolve(self):
-        dns_client_mock = Mock()
-
-        service_name = "test_service.example.com"
-        host_name = "example.com"
-
-        answer_srv = dns.RRHeader(
-            type=dns.SRV, payload=dns.Record_SRV(target=host_name)
-        )
-
-        dns_client_mock.lookupService.return_value = defer.succeed(
-            ([answer_srv], None, None)
-        )
-
-        cache = {}
-
-        servers = yield resolve_service(
-            service_name, dns_client=dns_client_mock, cache=cache
-        )
-
-        dns_client_mock.lookupService.assert_called_once_with(service_name)
-
-        self.assertEquals(len(servers), 1)
-        self.assertEquals(servers, cache[service_name])
-        self.assertEquals(servers[0].host, host_name)
-
-    @defer.inlineCallbacks
-    def test_from_cache_expired_and_dns_fail(self):
-        dns_client_mock = Mock()
-        dns_client_mock.lookupService.return_value = defer.fail(error.DNSServerError())
-
-        service_name = "test_service.example.com"
-
-        entry = Mock(spec_set=["expires"])
-        entry.expires = 0
-
-        cache = {service_name: [entry]}
-
-        servers = yield resolve_service(
-            service_name, dns_client=dns_client_mock, cache=cache
-        )
-
-        dns_client_mock.lookupService.assert_called_once_with(service_name)
-
-        self.assertEquals(len(servers), 1)
-        self.assertEquals(servers, cache[service_name])
-
-    @defer.inlineCallbacks
-    def test_from_cache(self):
-        clock = MockClock()
-
-        dns_client_mock = Mock(spec_set=['lookupService'])
-        dns_client_mock.lookupService = Mock(spec_set=[])
-
-        service_name = "test_service.example.com"
-
-        entry = Mock(spec_set=["expires"])
-        entry.expires = 999999999
-
-        cache = {service_name: [entry]}
-
-        servers = yield resolve_service(
-            service_name, dns_client=dns_client_mock, cache=cache, clock=clock
-        )
-
-        self.assertFalse(dns_client_mock.lookupService.called)
-
-        self.assertEquals(len(servers), 1)
-        self.assertEquals(servers, cache[service_name])
-
-    @defer.inlineCallbacks
-    def test_empty_cache(self):
-        dns_client_mock = Mock()
-
-        dns_client_mock.lookupService.return_value = defer.fail(error.DNSServerError())
-
-        service_name = "test_service.example.com"
-
-        cache = {}
-
-        with self.assertRaises(error.DNSServerError):
-            yield resolve_service(service_name, dns_client=dns_client_mock, cache=cache)
-
-    @defer.inlineCallbacks
-    def test_name_error(self):
-        dns_client_mock = Mock()
-
-        dns_client_mock.lookupService.return_value = defer.fail(error.DNSNameError())
-
-        service_name = "test_service.example.com"
-
-        cache = {}
-
-        servers = yield resolve_service(
-            service_name, dns_client=dns_client_mock, cache=cache
-        )
-
-        self.assertEquals(len(servers), 0)
-        self.assertEquals(len(cache), 0)
diff --git a/tests/test_event_auth.py b/tests/test_event_auth.py
index 411b4a9f..7ee318e4 100644
--- a/tests/test_event_auth.py
+++ b/tests/test_event_auth.py
@@ -16,6 +16,7 @@
 import unittest
 
 from synapse import event_auth
+from synapse.api.constants import RoomVersions
 from synapse.api.errors import AuthError
 from synapse.events import FrozenEvent
 
@@ -35,12 +36,16 @@ class EventAuthTestCase(unittest.TestCase):
         }
 
         # creator should be able to send state
-        event_auth.check(_random_state_event(creator), auth_events, do_sig_check=False)
+        event_auth.check(
+            RoomVersions.V1, _random_state_event(creator), auth_events,
+            do_sig_check=False,
+        )
 
         # joiner should not be able to send state
         self.assertRaises(
             AuthError,
             event_auth.check,
+            RoomVersions.V1,
             _random_state_event(joiner),
             auth_events,
             do_sig_check=False,
@@ -69,13 +74,17 @@ class EventAuthTestCase(unittest.TestCase):
         self.assertRaises(
             AuthError,
             event_auth.check,
+            RoomVersions.V1,
             _random_state_event(pleb),
             auth_events,
             do_sig_check=False,
         ),
 
         # king should be able to send state
-        event_auth.check(_random_state_event(king), auth_events, do_sig_check=False)
+        event_auth.check(
+            RoomVersions.V1, _random_state_event(king), auth_events,
+            do_sig_check=False,
+        )
 
 
 # helpers for making events
diff --git a/tests/test_server.py b/tests/test_server.py
index 634a8fbc..08fb3fe0 100644
--- a/tests/test_server.py
+++ b/tests/test_server.py
@@ -19,7 +19,7 @@ from six import StringIO
 
 from twisted.internet.defer import Deferred
 from twisted.python.failure import Failure
-from twisted.test.proto_helpers import AccumulatingProtocol, MemoryReactorClock
+from twisted.test.proto_helpers import AccumulatingProtocol
 from twisted.web.resource import Resource
 from twisted.web.server import NOT_DONE_YET
 
@@ -30,12 +30,18 @@ from synapse.util import Clock
 from synapse.util.logcontext import make_deferred_yieldable
 
 from tests import unittest
-from tests.server import FakeTransport, make_request, render, setup_test_homeserver
+from tests.server import (
+    FakeTransport,
+    ThreadedMemoryReactorClock,
+    make_request,
+    render,
+    setup_test_homeserver,
+)
 
 
 class JsonResourceTests(unittest.TestCase):
     def setUp(self):
-        self.reactor = MemoryReactorClock()
+        self.reactor = ThreadedMemoryReactorClock()
         self.hs_clock = Clock(self.reactor)
         self.homeserver = setup_test_homeserver(
             self.addCleanup, http_client=None, clock=self.hs_clock, reactor=self.reactor
diff --git a/tests/test_utils/__init__.py b/tests/test_utils/__init__.py
new file mode 100644
index 00000000..a7310cf1
--- /dev/null
+++ b/tests/test_utils/__init__.py
@@ -0,0 +1,18 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+Utilities for running the unit tests
+"""
diff --git a/tests/test_utils/logging_setup.py b/tests/test_utils/logging_setup.py
new file mode 100644
index 00000000..d0bc8e21
--- /dev/null
+++ b/tests/test_utils/logging_setup.py
@@ -0,0 +1,54 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import logging
+import os
+
+import twisted.logger
+
+from synapse.util.logcontext import LoggingContextFilter
+
+
+class ToTwistedHandler(logging.Handler):
+    """logging handler which sends the logs to the twisted log"""
+    tx_log = twisted.logger.Logger()
+
+    def emit(self, record):
+        log_entry = self.format(record)
+        log_level = record.levelname.lower().replace('warning', 'warn')
+        self.tx_log.emit(
+            twisted.logger.LogLevel.levelWithName(log_level),
+            log_entry.replace("{", r"(").replace("}", r")"),
+        )
+
+
+def setup_logging():
+    """Configure the python logging appropriately for the tests.
+
+    (Logs will end up in _trial_temp.)
+    """
+    root_logger = logging.getLogger()
+
+    log_format = (
+        "%(asctime)s - %(name)s - %(lineno)d - %(levelname)s - %(request)s - %(message)s"
+    )
+
+    handler = ToTwistedHandler()
+    formatter = logging.Formatter(log_format)
+    handler.setFormatter(formatter)
+    handler.addFilter(LoggingContextFilter(request=""))
+    root_logger.addHandler(handler)
+
+    log_level = os.environ.get("SYNAPSE_TEST_LOG_LEVEL", "ERROR")
+    root_logger.setLevel(log_level)
diff --git a/tests/test_visibility.py b/tests/test_visibility.py
index 2eea3b09..455db9f2 100644
--- a/tests/test_visibility.py
+++ b/tests/test_visibility.py
@@ -17,6 +17,7 @@ import logging
 from twisted.internet import defer
 from twisted.internet.defer import succeed
 
+from synapse.api.constants import RoomVersions
 from synapse.events import FrozenEvent
 from synapse.visibility import filter_events_for_server
 
@@ -124,6 +125,7 @@ class FilterEventsForServerTestCase(tests.unittest.TestCase):
     def inject_visibility(self, user_id, visibility):
         content = {"history_visibility": visibility}
         builder = self.event_builder_factory.new(
+            RoomVersions.V1,
             {
                 "type": "m.room.history_visibility",
                 "sender": user_id,
@@ -144,6 +146,7 @@ class FilterEventsForServerTestCase(tests.unittest.TestCase):
         content = {"membership": membership}
         content.update(extra_content)
         builder = self.event_builder_factory.new(
+            RoomVersions.V1,
             {
                 "type": "m.room.member",
                 "sender": user_id,
@@ -163,8 +166,9 @@ class FilterEventsForServerTestCase(tests.unittest.TestCase):
     @defer.inlineCallbacks
     def inject_message(self, user_id, content=None):
         if content is None:
-            content = {"body": "testytest"}
+            content = {"body": "testytest", "msgtype": "m.text"}
         builder = self.event_builder_factory.new(
+            RoomVersions.V1,
             {
                 "type": "m.room.message",
                 "sender": user_id,
diff --git a/tests/unittest.py b/tests/unittest.py
index 78d2f740..fac254ff 100644
--- a/tests/unittest.py
+++ b/tests/unittest.py
@@ -31,38 +31,14 @@ from synapse.http.server import JsonResource
 from synapse.http.site import SynapseRequest
 from synapse.server import HomeServer
 from synapse.types import UserID, create_requester
-from synapse.util.logcontext import LoggingContext, LoggingContextFilter
+from synapse.util.logcontext import LoggingContext
 
 from tests.server import get_clock, make_request, render, setup_test_homeserver
+from tests.test_utils.logging_setup import setup_logging
 from tests.utils import default_config, setupdb
 
 setupdb()
-
-# Set up putting Synapse's logs into Trial's.
-rootLogger = logging.getLogger()
-
-log_format = (
-    "%(asctime)s - %(name)s - %(lineno)d - %(levelname)s - %(request)s - %(message)s"
-)
-
-
-class ToTwistedHandler(logging.Handler):
-    tx_log = twisted.logger.Logger()
-
-    def emit(self, record):
-        log_entry = self.format(record)
-        log_level = record.levelname.lower().replace('warning', 'warn')
-        self.tx_log.emit(
-            twisted.logger.LogLevel.levelWithName(log_level),
-            log_entry.replace("{", r"(").replace("}", r")"),
-        )
-
-
-handler = ToTwistedHandler()
-formatter = logging.Formatter(log_format)
-handler.setFormatter(formatter)
-handler.addFilter(LoggingContextFilter(request=""))
-rootLogger.addHandler(handler)
+setup_logging()
 
 
 def around(target):
@@ -96,7 +72,7 @@ class TestCase(unittest.TestCase):
 
         method = getattr(self, methodName)
 
-        level = getattr(method, "loglevel", getattr(self, "loglevel", logging.ERROR))
+        level = getattr(method, "loglevel", getattr(self, "loglevel", None))
 
         @around(self)
         def setUp(orig):
@@ -114,7 +90,7 @@ class TestCase(unittest.TestCase):
                 )
 
             old_level = logging.getLogger().level
-            if old_level != level:
+            if level is not None and old_level != level:
 
                 @around(self)
                 def tearDown(orig):
@@ -122,7 +98,8 @@ class TestCase(unittest.TestCase):
                     logging.getLogger().setLevel(old_level)
                     return ret
 
-            logging.getLogger().setLevel(level)
+                logging.getLogger().setLevel(level)
+
             return orig()
 
         @around(self)
@@ -333,7 +310,15 @@ class HomeserverTestCase(TestCase):
         """
         kwargs = dict(kwargs)
         kwargs.update(self._hs_args)
-        return setup_test_homeserver(self.addCleanup, *args, **kwargs)
+        hs = setup_test_homeserver(self.addCleanup, *args, **kwargs)
+        stor = hs.get_datastore()
+
+        # Run the database background updates.
+        if hasattr(stor, "do_next_background_update"):
+            while not self.get_success(stor.has_completed_background_updates()):
+                self.get_success(stor.do_next_background_update(1))
+
+        return hs
 
     def pump(self, by=0.0):
         """
diff --git a/tests/util/caches/test_ttlcache.py b/tests/util/caches/test_ttlcache.py
new file mode 100644
index 00000000..03b3c15d
--- /dev/null
+++ b/tests/util/caches/test_ttlcache.py
@@ -0,0 +1,83 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from mock import Mock
+
+from synapse.util.caches.ttlcache import TTLCache
+
+from tests import unittest
+
+
+class CacheTestCase(unittest.TestCase):
+    def setUp(self):
+        self.mock_timer = Mock(side_effect=lambda: 100.0)
+        self.cache = TTLCache("test_cache", self.mock_timer)
+
+    def test_get(self):
+        """simple set/get tests"""
+        self.cache.set('one', '1', 10)
+        self.cache.set('two', '2', 20)
+        self.cache.set('three', '3', 30)
+
+        self.assertEqual(len(self.cache), 3)
+
+        self.assertTrue('one' in self.cache)
+        self.assertEqual(self.cache.get('one'), '1')
+        self.assertEqual(self.cache['one'], '1')
+        self.assertEqual(self.cache.get_with_expiry('one'), ('1', 110))
+        self.assertEqual(self.cache._metrics.hits, 3)
+        self.assertEqual(self.cache._metrics.misses, 0)
+
+        self.cache.set('two', '2.5', 20)
+        self.assertEqual(self.cache['two'], '2.5')
+        self.assertEqual(self.cache._metrics.hits, 4)
+
+        # non-existent-item tests
+        self.assertEqual(self.cache.get('four', '4'), '4')
+        self.assertIs(self.cache.get('four', None), None)
+
+        with self.assertRaises(KeyError):
+            self.cache['four']
+
+        with self.assertRaises(KeyError):
+            self.cache.get('four')
+
+        with self.assertRaises(KeyError):
+            self.cache.get_with_expiry('four')
+
+        self.assertEqual(self.cache._metrics.hits, 4)
+        self.assertEqual(self.cache._metrics.misses, 5)
+
+    def test_expiry(self):
+        self.cache.set('one', '1', 10)
+        self.cache.set('two', '2', 20)
+        self.cache.set('three', '3', 30)
+
+        self.assertEqual(len(self.cache), 3)
+        self.assertEqual(self.cache['one'], '1')
+        self.assertEqual(self.cache['two'], '2')
+
+        # enough for the first entry to expire, but not the rest
+        self.mock_timer.side_effect = lambda: 110.0
+
+        self.assertEqual(len(self.cache), 2)
+        self.assertFalse('one' in self.cache)
+        self.assertEqual(self.cache['two'], '2')
+        self.assertEqual(self.cache['three'], '3')
+
+        self.assertEqual(self.cache.get_with_expiry('two'), ('2', 120))
+
+        self.assertEqual(self.cache._metrics.hits, 5)
+        self.assertEqual(self.cache._metrics.misses, 0)
diff --git a/tests/util/test_async_utils.py b/tests/util/test_async_utils.py
new file mode 100644
index 00000000..84dd71e4
--- /dev/null
+++ b/tests/util/test_async_utils.py
@@ -0,0 +1,104 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from twisted.internet import defer
+from twisted.internet.defer import CancelledError, Deferred
+from twisted.internet.task import Clock
+
+from synapse.util import logcontext
+from synapse.util.async_helpers import timeout_deferred
+from synapse.util.logcontext import LoggingContext
+
+from tests.unittest import TestCase
+
+
+class TimeoutDeferredTest(TestCase):
+    def setUp(self):
+        self.clock = Clock()
+
+    def test_times_out(self):
+        """Basic test case that checks that the original deferred is cancelled and that
+        the timing-out deferred is errbacked
+        """
+        cancelled = [False]
+
+        def canceller(_d):
+            cancelled[0] = True
+
+        non_completing_d = Deferred(canceller)
+        timing_out_d = timeout_deferred(non_completing_d, 1.0, self.clock)
+
+        self.assertNoResult(timing_out_d)
+        self.assertFalse(cancelled[0], "deferred was cancelled prematurely")
+
+        self.clock.pump((1.0, ))
+
+        self.assertTrue(cancelled[0], "deferred was not cancelled by timeout")
+        self.failureResultOf(timing_out_d, defer.TimeoutError, )
+
+    def test_times_out_when_canceller_throws(self):
+        """Test that we have successfully worked around
+        https://twistedmatrix.com/trac/ticket/9534"""
+
+        def canceller(_d):
+            raise Exception("can't cancel this deferred")
+
+        non_completing_d = Deferred(canceller)
+        timing_out_d = timeout_deferred(non_completing_d, 1.0, self.clock)
+
+        self.assertNoResult(timing_out_d)
+
+        self.clock.pump((1.0, ))
+
+        self.failureResultOf(timing_out_d, defer.TimeoutError, )
+
+    def test_logcontext_is_preserved_on_cancellation(self):
+        blocking_was_cancelled = [False]
+
+        @defer.inlineCallbacks
+        def blocking():
+            non_completing_d = Deferred()
+            with logcontext.PreserveLoggingContext():
+                try:
+                    yield non_completing_d
+                except CancelledError:
+                    blocking_was_cancelled[0] = True
+                    raise
+
+        with logcontext.LoggingContext("one") as context_one:
+            # the errbacks should be run in the test logcontext
+            def errback(res, deferred_name):
+                self.assertIs(
+                    LoggingContext.current_context(), context_one,
+                    "errback %s run in unexpected logcontext %s" % (
+                        deferred_name, LoggingContext.current_context(),
+                    )
+                )
+                return res
+
+            original_deferred = blocking()
+            original_deferred.addErrback(errback, "orig")
+            timing_out_d = timeout_deferred(original_deferred, 1.0, self.clock)
+            self.assertNoResult(timing_out_d)
+            self.assertIs(LoggingContext.current_context(), LoggingContext.sentinel)
+            timing_out_d.addErrback(errback, "timingout")
+
+            self.clock.pump((1.0, ))
+
+            self.assertTrue(
+                blocking_was_cancelled[0],
+                "non-completing deferred was not cancelled",
+            )
+            self.failureResultOf(timing_out_d, defer.TimeoutError, )
+            self.assertIs(LoggingContext.current_context(), context_one)
diff --git a/tests/utils.py b/tests/utils.py
index 08d6faa0..2dfcb70a 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -26,7 +26,7 @@ from six.moves.urllib import parse as urlparse
 
 from twisted.internet import defer, reactor
 
-from synapse.api.constants import EventTypes
+from synapse.api.constants import EventTypes, RoomVersions
 from synapse.api.errors import CodeMessageException, cs_error
 from synapse.config.server import ServerConfig
 from synapse.federation.transport import server
@@ -154,7 +154,9 @@ def default_config(name):
     config.update_user_directory = False
 
     def is_threepid_reserved(threepid):
-        return ServerConfig.is_threepid_reserved(config, threepid)
+        return ServerConfig.is_threepid_reserved(
+            config.mau_limits_reserved_threepids, threepid
+        )
 
     config.is_threepid_reserved.side_effect = is_threepid_reserved
 
@@ -622,6 +624,7 @@ def create_room(hs, room_id, creator_id):
     event_creation_handler = hs.get_event_creation_handler()
 
     builder = event_builder_factory.new(
+        RoomVersions.V1,
         {
             "type": EventTypes.Create,
             "state_key": "",
diff --git a/tox.ini b/tox.ini
index a0f54868..9b2d78ed 100644
--- a/tox.ini
+++ b/tox.ini
@@ -149,4 +149,5 @@ deps =
     codecov
 commands =
     coverage combine
+    coverage xml
     codecov -X gcov