.ci/before_build_wheel.sh

+#!/bin/sh
+set -xeu
+
+# On 32-bit Linux platforms, we need libatomic1 to use rustup
+if command -v yum &> /dev/null; then
+   yum install -y libatomic
+fi
+
+# Install a Rust toolchain
+curl https://sh.rustup.rs -sSf | sh -s -- --default-toolchain 1.82.0 -y --profile minimal

.ci/scripts/auditwheel_wrapper.py

 #!/usr/bin/env python
-# Copyright 2022 The Matrix.org Foundation C.I.C.
 #
-# 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
+# This file is licensed under the Affero General Public License (AGPL) version 3.
+#
+# Copyright (C) 2023 New Vector, Ltd
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# See the GNU Affero General Public License for more details:
+# <https://www.gnu.org/licenses/agpl-3.0.html>.
+#
+# Originally licensed under the Apache License, Version 2.0:
+# <http://www.apache.org/licenses/LICENSE-2.0>.
+#
+# [This file includes modifications made by New Vector Limited]
 #
-#     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.
 
 # Wraps `auditwheel repair` to first check if we're repairing a potentially abi3
 # compatible wheel, if so rename the wheel before repairing it.
@@ -50,7 +56,16 @@ def cpython(wheel_file: str, name: str, version: Version, tag: Tag) -> str:
 
     check_is_abi3_compatible(wheel_file)
 
-    abi3_tag = Tag(tag.interpreter, "abi3", tag.platform)
+    # HACK: it seems that some older versions of pip will consider a wheel marked
+    # as macosx_11_0 as incompatible with Big Sur. I haven't done the full archaeology
+    # here; there are some clues in
+    #     https://github.com/pantsbuild/pants/pull/12857
+    #     https://github.com/pypa/pip/issues/9138
+    #     https://github.com/pypa/packaging/pull/319
+    # Empirically this seems to work, note that macOS 11 and 10.16 are the same,
+    # both versions are valid for backwards compatibility.
+    platform = tag.platform.replace("macosx_11_0", "macosx_10_16")
+    abi3_tag = Tag(tag.interpreter, "abi3", platform)
 
     dirname = os.path.dirname(wheel_file)
     new_wheel_file = os.path.join(

.ci/scripts/calculate_jobs.py

 #!/usr/bin/env python
-# Copyright 2022 The Matrix.org Foundation C.I.C.
 #
-# 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
+# This file is licensed under the Affero General Public License (AGPL) version 3.
+#
+# Copyright (C) 2023 New Vector, Ltd
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# See the GNU Affero General Public License for more details:
+# <https://www.gnu.org/licenses/agpl-3.0.html>.
+#
+# Originally licensed under the Apache License, Version 2.0:
+# <http://www.apache.org/licenses/LICENSE-2.0>.
+#
+# [This file includes modifications made by New Vector Limited]
 #
-#     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.
 
 # Calculate the trial jobs to run based on if we're in a PR or not.
 
@@ -29,11 +35,12 @@ IS_PR = os.environ["GITHUB_REF"].startswith("refs/pull/")
 
 # First calculate the various trial jobs.
 #
-# For each type of test we only run on Py3.7 on PRs
+# For PRs, we only run each type of test with the oldest Python version supported (which
+# is Python 3.9 right now)
 
 trial_sqlite_tests = [
     {
-        "python-version": "3.7",
+        "python-version": "3.9",
         "database": "sqlite",
         "extras": "all",
     }
@@ -46,15 +53,14 @@ if not IS_PR:
             "database": "sqlite",
             "extras": "all",
         }
-        for version in ("3.8", "3.9", "3.10")
+        for version in ("3.10", "3.11", "3.12", "3.13")
     )
 
-
 trial_postgres_tests = [
     {
-        "python-version": "3.7",
+        "python-version": "3.9",
         "database": "postgres",
-        "postgres-version": "10",
+        "postgres-version": "13",
         "extras": "all",
     }
 ]
@@ -62,16 +68,16 @@ trial_postgres_tests = [
 if not IS_PR:
     trial_postgres_tests.append(
         {
-            "python-version": "3.10",
+            "python-version": "3.13",
             "database": "postgres",
-            "postgres-version": "14",
+            "postgres-version": "17",
             "extras": "all",
         }
     )
 
 trial_no_extra_tests = [
     {
-        "python-version": "3.7",
+        "python-version": "3.9",
         "database": "sqlite",
         "extras": "",
     }
@@ -93,35 +99,45 @@ set_output("trial_test_matrix", test_matrix)
 
 # First calculate the various sytest jobs.
 #
-# For each type of test we only run on focal on PRs
+# For each type of test we only run on bullseye on PRs
 
 
 sytest_tests = [
     {
-        "sytest-tag": "focal",
+        "sytest-tag": "bullseye",
     },
     {
-        "sytest-tag": "focal",
+        "sytest-tag": "bullseye",
         "postgres": "postgres",
     },
     {
-        "sytest-tag": "focal",
+        "sytest-tag": "bullseye",
         "postgres": "multi-postgres",
         "workers": "workers",
     },
+    {
+        "sytest-tag": "bullseye",
+        "postgres": "multi-postgres",
+        "workers": "workers",
+        "reactor": "asyncio",
+    },
 ]
 
 if not IS_PR:
     sytest_tests.extend(
         [
             {
-                "sytest-tag": "testing",
+                "sytest-tag": "bullseye",
+                "reactor": "asyncio",
+            },
+            {
+                "sytest-tag": "bullseye",
                 "postgres": "postgres",
+                "reactor": "asyncio",
             },
             {
-                "sytest-tag": "buster",
-                "postgres": "multi-postgres",
-                "workers": "workers",
+                "sytest-tag": "testing",
+                "postgres": "postgres",
             },
         ]
     )

.ci/scripts/check_lockfile.py

+#! /usr/bin/env python
+import sys
+
+if sys.version_info < (3, 11):
+    raise RuntimeError("Requires at least Python 3.11, to import tomllib")
+
+import tomllib
+
+with open("poetry.lock", "rb") as f:
+    lockfile = tomllib.load(f)
+
+try:
+    lock_version = lockfile["metadata"]["lock-version"]
+    assert lock_version == "2.0"
+except Exception:
+    print(
+        """\
+    Lockfile is not version 2.0. You probably need to upgrade poetry on your local box
+    and re-run `poetry lock --no-update`. See the Poetry cheat sheet at
+    https://element-hq.github.io/synapse/develop/development/dependencies.html
+    """
+    )
+    raise

.ci/scripts/prepare_old_deps.sh

 #!/usr/bin/env bash
-# this script is run by GitHub Actions in a plain `focal` container; it
+# this script is run by GitHub Actions in a plain `jammy` container; it
 # - installs the minimal system requirements, and poetry;
 # - patches the project definition file to refer to old versions only;
 # - creates a venv with these old versions using poetry; and finally
@@ -31,34 +31,6 @@ sed -i \
    -e '/systemd/d' \
    pyproject.toml
 
-# Use poetry to do the installation. This ensures that the versions are all mutually
-# compatible (as far the package metadata declares, anyway); pip's package resolver
-# is more lax.
-#
-# Rather than `poetry install --no-dev`, we drop all dev dependencies from the
-# toml file. This means we don't have to ensure compatibility between old deps and
-# dev tools.
-
-pip install toml wheel
-
-REMOVE_DEV_DEPENDENCIES="
-import toml
-with open('pyproject.toml', 'r') as f:
-    data = toml.loads(f.read())
-
-del data['tool']['poetry']['dev-dependencies']
-
-with open('pyproject.toml', 'w') as f:
-    toml.dump(data, f)
-"
-python3 -c "$REMOVE_DEV_DEPENDENCIES"
-
-pip install poetry==1.2.0
-poetry lock
-
 echo "::group::Patched pyproject.toml"
 cat pyproject.toml
 echo "::endgroup::"
-echo "::group::Lockfile after patch"
-cat poetry.lock
-echo "::endgroup::"

.ci/scripts/setup_complement_prerequisites.sh

@@ -9,19 +9,9 @@ set -eu
 alias block='{ set +x; } 2>/dev/null; func() { echo "::group::$*"; set -x; }; func'
 alias endblock='{ set +x; } 2>/dev/null; func() { echo "::endgroup::"; set -x; }; func'
 
-block Set Go Version
-  # The path is set via a file given by $GITHUB_PATH. We need both Go 1.17 and GOPATH on the path to run Complement.
-  # See https://docs.github.com/en/actions/using-workflows/workflow-commands-for-github-actions#adding-a-system-path
-
-  # Add Go 1.17 to the PATH: see https://github.com/actions/virtual-environments/blob/main/images/linux/Ubuntu2004-Readme.md#environment-variables-2
-  echo "$GOROOT_1_17_X64/bin" >> $GITHUB_PATH
-  # Add the Go path to the PATH: We need this so we can call gotestfmt
-  echo "~/go/bin" >> $GITHUB_PATH
-endblock
-
 block Install Complement Dependencies
   sudo apt-get -qq update && sudo apt-get install -qqy libolm3 libolm-dev
-  go get -v github.com/gotesttools/gotestfmt/v2/cmd/gotestfmt@latest
+  go install -v github.com/gotesttools/gotestfmt/v2/cmd/gotestfmt@latest
 endblock
 
 block Install custom gotestfmt template

.ci/scripts/test_export_data_command.sh

@@ -23,8 +23,9 @@ poetry run python -m synapse.app.admin_cmd -c .ci/sqlite-config.yaml  export-dat
 --output-directory /tmp/export_data
 
 # Test that the output directory exists and contains the rooms directory
-dir="/tmp/export_data/rooms"
-if [ -d "$dir" ]; then
+dir_r="/tmp/export_data/rooms"
+dir_u="/tmp/export_data/user_data"
+if [ -d "$dir_r" ] && [ -d "$dir_u" ]; then
   echo "Command successful, this test passes"
 else
   echo "No output directories found, the command fails against a sqlite database."
@@ -43,8 +44,9 @@ poetry run python -m synapse.app.admin_cmd -c .ci/postgres-config.yaml  export-d
 --output-directory /tmp/export_data2
 
 # Test that the output directory exists and contains the rooms directory
-dir2="/tmp/export_data2/rooms"
-if [ -d "$dir2" ]; then
+dir_r2="/tmp/export_data2/rooms"
+dir_u2="/tmp/export_data2/user_data"
+if [ -d "$dir_r2" ] && [ -d "$dir_u2" ]; then
   echo "Command successful, this test passes"
 else
   echo "No output directories found, the command fails against a postgres database."

.dockerignore

@@ -8,6 +8,7 @@
 !README.rst
 !pyproject.toml
 !poetry.lock
+!requirements.txt
 !Cargo.lock
 !Cargo.toml
 !build_rust.py

.editorconfig

@@ -4,7 +4,7 @@
 root = true
 
 # 4 space indentation
-[*.py]
+[*.{py,pyi}]
 indent_style = space
 indent_size = 4
 max_line_length = 88

.flake8

-# TODO: incorporate this into pyproject.toml if flake8 supports it in the future.
-# See https://github.com/PyCQA/flake8/issues/234
-[flake8]
-# see https://pycodestyle.readthedocs.io/en/latest/intro.html#error-codes
-# for error codes. The ones we ignore are:
-#  W503: line break before binary operator
-#  W504: line break after binary operator
-#  E203: whitespace before ':' (which is contrary to pep8?)
-#  E731: do not assign a lambda expression, use a def
-#  E501: Line too long (black enforces this for us)
-#
-# flake8-bugbear runs extra checks. Its error codes are described at
-# https://github.com/PyCQA/flake8-bugbear#list-of-warnings
-#  B019: Use of functools.lru_cache or functools.cache on methods can lead to memory leaks
-#  B023: Functions defined inside a loop must not use variables redefined in the loop
-#  B024: Abstract base class with no abstract method.
-
-ignore=W503,W504,E203,E731,E501,B019,B023,B024

.git-blame-ignore-revs

@@ -8,17 +8,21 @@
 # If ignoring a pull request that was not squash merged, only the merge
 # commit needs to be put here. Child commits will be resolved from it.
 
-# Run black (#3679).
+# Run black (https://github.com/matrix-org/synapse/pull/3679).
 8b3d9b6b199abb87246f982d5db356f1966db925
 
-# Black reformatting (#5482).
+# Black reformatting (https://github.com/matrix-org/synapse/pull/5482).
 32e7c9e7f20b57dd081023ac42d6931a8da9b3a3
 
-# Target Python 3.5 with black (#8664).
+# Target Python 3.5 with black (https://github.com/matrix-org/synapse/pull/8664).
 aff1eb7c671b0a3813407321d2702ec46c71fa56
 
-# Update black to 20.8b1 (#9381).
+# Update black to 20.8b1 (https://github.com/matrix-org/synapse/pull/9381).
 0a00b7ff14890987f09112a2ae696c61001e6cf1
 
-# Convert tests/rest/admin/test_room.py to unix file endings (#7953).
-c4268e3da64f1abb5b31deaeb5769adb6510c0a7
\ No newline at end of file
+# Convert tests/rest/admin/test_room.py to unix file endings (https://github.com/matrix-org/synapse/pull/7953).
+c4268e3da64f1abb5b31deaeb5769adb6510c0a7
+
+# Update black to 23.1.0 (https://github.com/matrix-org/synapse/pull/15103)
+9bb2eac71962970d02842bca441f4bcdbbf93a11
+

.github/CODEOWNERS

 # Automatically request reviews from the synapse-core team when a pull request comes in.
-* @matrix-org/synapse-core
\ No newline at end of file
+* @element-hq/synapse-core

.github/FUNDING.yml

-# One username per supported platform and one custom link
-patreon: matrixdotorg
-liberapay: matrixdotorg
-custom: https://paypal.me/matrixdotorg

.github/ISSUE_TEMPLATE.md

@@ -2,4 +2,4 @@
 (using a matrix.org account if necessary). We do not use GitHub issues for
 support.
 
-**If you want to report a security issue** please see https://matrix.org/security-disclosure-policy/
+**If you want to report a security issue** please see https://element.io/security/security-disclosure-policy

.github/ISSUE_TEMPLATE/BUG_REPORT.yml

@@ -7,7 +7,7 @@ body:
         **THIS IS NOT A SUPPORT CHANNEL!**
         **IF YOU HAVE SUPPORT QUESTIONS ABOUT RUNNING OR CONFIGURING YOUR OWN HOME SERVER**, please ask in **[#synapse:matrix.org](https://matrix.to/#/#synapse:matrix.org)** (using a matrix.org account if necessary).
 
-        If you want to report a security issue, please see https://matrix.org/security-disclosure-policy/
+        If you want to report a security issue, please see https://element.io/security/security-disclosure-policy
 
         This is a bug report form. By following the instructions below and completing the sections with your information, you will help the us to get all the necessary data to fix your issue.
 
@@ -74,6 +74,36 @@ body:
         - Debian packages from packages.matrix.org
         - pip (from PyPI)
         - Other (please mention below)
+        - I don't know
+    validations:
+      required: true
+  - type: input
+    id: database
+    attributes:
+      label: Database
+      description: |
+        Are you using SQLite or PostgreSQL? What's the version of your database?
+
+        If PostgreSQL, please also answer the following:
+         - are you using a single PostgreSQL server
+        or [separate servers for `main` and `state`](https://element-hq.github.io/synapse/latest/usage/configuration/config_documentation.html#databases)?
+         - have you previously ported from SQLite using the Synapse "portdb" script?
+         - have you previously restored from a backup?
+    validations:
+      required: true
+  - type: dropdown
+    id: workers
+    attributes:
+      label: Workers
+      description: |
+        Are you running a single Synapse process, or are you running
+        [2 or more workers](https://element-hq.github.io/synapse/latest/workers.html)?
+      options:
+        - Single process
+        - Multiple workers
+        - I don't know
+    validations:
+      required: true
   - type: textarea
     id: platform
     attributes:
@@ -83,17 +113,28 @@ body:
         e.g. distro, hardware, if it's running in a vm/container, etc.
     validations:
       required: true
+  - type: textarea
+    id: config
+    attributes:
+      label: Configuration
+      description: |
+        Do you have any unusual config options turned on? If so, please provide details.
+
+        - Experimental or undocumented features
+        - [Presence](https://element-hq.github.io/synapse/latest/usage/configuration/config_documentation.html#presence)
+        - [Message retention](https://element-hq.github.io/synapse/latest/message_retention_policies.html)
+        - [Synapse modules](https://element-hq.github.io/synapse/latest/modules/index.html)
   - type: textarea
     id: logs
     attributes:
       label: Relevant log output
       description: |
-        Please copy and paste any relevant log output, ideally at INFO or DEBUG log level.
-        This will be automatically formatted into code, so there is no need for backticks.
+        Please copy and paste any relevant log output as text (not images), ideally at INFO or DEBUG log level.
+        This will be automatically formatted into code, so there is no need for backticks (`\``).
 
         Please be careful to remove any personal or private data.
 
-        **Bug reports are usually very difficult to diagnose without logging.**
+        **Bug reports are usually impossible to diagnose without logging.**
       render: shell
     validations:
       required: true

.github/PULL_REQUEST_TEMPLATE.md

 ### Pull Request Checklist
 
-<!-- Please read https://matrix-org.github.io/synapse/latest/development/contributing_guide.html before submitting your pull request -->
+<!-- Please read https://element-hq.github.io/synapse/latest/development/contributing_guide.html before submitting your pull request -->
 
 * [ ] Pull request is based on the develop branch
-* [ ] Pull request includes a [changelog file](https://matrix-org.github.io/synapse/latest/development/contributing_guide.html#changelog). The entry should:
+* [ ] Pull request includes a [changelog file](https://element-hq.github.io/synapse/latest/development/contributing_guide.html#changelog). The entry should:
   - Be a short description of your change which makes sense to users. "Fixed a bug that prevented receiving messages from other servers." instead of "Moved X method from `EventStore` to `EventWorkerStore`.".
   - Use markdown where necessary, mostly for `code blocks`.
   - End with either a period (.) or an exclamation mark (!).
   - Start with a capital letter.
   - Feel free to credit yourself, by adding a sentence "Contributed by @github_username." or "Contributed by [Your Name]." to the end of the entry.
-* [ ] Pull request includes a [sign off](https://matrix-org.github.io/synapse/latest/development/contributing_guide.html#sign-off)
-* [ ] [Code style](https://matrix-org.github.io/synapse/latest/code_style.html) is correct
-  (run the [linters](https://matrix-org.github.io/synapse/latest/development/contributing_guide.html#run-the-linters))
+* [ ] [Code style](https://element-hq.github.io/synapse/latest/code_style.html) is correct
+  (run the [linters](https://element-hq.github.io/synapse/latest/development/contributing_guide.html#run-the-linters))

.github/dependabot.yml

@@ -18,5 +18,6 @@ updates:
 
   - package-ecosystem: "cargo"
     directory: "/"
+    versioning-strategy: "lockfile-only"
     schedule:
       interval: "weekly"

.github/workflows/dependabot_changelog.yml

-name: Write changelog for dependabot PR
-on:
-  pull_request:
-    types:
-      - opened
-      - reopened  # For debugging!
-
-permissions:
-  # Needed to be able to push the commit. See 
-  #     https://docs.github.com/en/code-security/dependabot/working-with-dependabot/automating-dependabot-with-github-actions#enable-auto-merge-on-a-pull-request
-  # for a similar example
-  contents: write
-
-jobs:
-  add-changelog:
-    runs-on: 'ubuntu-latest'
-    if: ${{ github.actor == 'dependabot[bot]' }}
-    steps:
-      - uses: actions/checkout@v3
-        with:
-          ref: ${{ github.event.pull_request.head.ref }}
-      - name: Write, commit and push changelog
-        run: |
-          echo "${{ github.event.pull_request.title }}." > "changelog.d/${{ github.event.pull_request.number }}".misc
-          git add changelog.d
-          git config user.email "github-actions[bot]@users.noreply.github.com"
-          git config user.name "GitHub Actions"
-          git commit -m "Changelog"
-          git push
-        shell: bash
-      # The `git push` above does not trigger CI on the dependabot PR.
-      #
-      # By default, workflows can't trigger other workflows when they're just using the
-      # default `GITHUB_TOKEN` access token. (This is intended to stop you from writing
-      # recursive workflow loops by accident, because that'll get very expensive very
-      # quickly.) Instead, you have to manually call out to another workflow, or else
-      # make your changes (i.e. the `git push` above) using a personal access token.
-      # See
-      # https://docs.github.com/en/actions/using-workflows/triggering-a-workflow#triggering-a-workflow-from-a-workflow
-      #
-      # I have tried and failed to find a way to trigger CI on the "merge ref" of the PR.
-      # See git commit history for previous attempts. If anyone desperately wants to try
-      # again in the future, make a matrix-bot account and use its access token to git push.
-
-  # THIS WORKFLOW HAS WRITE PERMISSIONS---do not add other jobs here unless they
-  # are sufficiently locked down to dependabot only as above.

.github/workflows/docker.yml

@@ -10,35 +10,58 @@ on:
 
 permissions:
   contents: read
-
+  packages: write
+  id-token: write # needed for signing the images with GitHub OIDC Token
 jobs:
   build:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
       - name: Set up QEMU
         id: qemu
-        uses: docker/setup-qemu-action@v2
+        uses: docker/setup-qemu-action@v3
         with:
           platforms: arm64
 
       - name: Set up Docker Buildx
         id: buildx
-        uses: docker/setup-buildx-action@v2
+        uses: docker/setup-buildx-action@v3
 
       - name: Inspect builder
         run: docker buildx inspect
 
+      - name: Install Cosign
+        uses: sigstore/cosign-installer@v3.8.1
+
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Extract version from pyproject.toml
+        # Note: explicitly requesting bash will mean bash is invoked with `-eo pipefail`, see
+        # https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idstepsshell
+        shell: bash
+        run: |
+          echo "SYNAPSE_VERSION=$(grep "^version" pyproject.toml | sed -E 's/version\s*=\s*["]([^"]*)["]/\1/')" >> $GITHUB_ENV
+
       - name: Log in to DockerHub
-        uses: docker/login-action@v2
+        uses: docker/login-action@v3
         with:
           username: ${{ secrets.DOCKERHUB_USERNAME }}
           password: ${{ secrets.DOCKERHUB_TOKEN }}
 
+      - name: Log in to GHCR
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
       - name: Calculate docker image tag
         id: set-tag
         uses: docker/metadata-action@master
         with:
-          images: matrixdotorg/synapse
+          images: |
+            docker.io/matrixdotorg/synapse
+            ghcr.io/element-hq/synapse
           flavor: |
             latest=false
           tags: |
@@ -48,10 +71,13 @@ jobs:
             type=pep440,pattern={{raw}}
 
       - name: Build and push all platforms
-        uses: docker/build-push-action@v3
+        id: build-and-push
+        uses: docker/build-push-action@v6
         with:
           push: true
-          labels: "gitsha1=${{ github.sha }}"
+          labels: |
+            gitsha1=${{ github.sha }}
+            org.opencontainers.image.version=${{ env.SYNAPSE_VERSION }}
           tags: "${{ steps.set-tag.outputs.tags }}"
           file: "docker/Dockerfile"
           platforms: linux/amd64,linux/arm64
@@ -60,3 +86,14 @@ jobs:
           # https://github.com/rust-lang/cargo/issues/10583
           build-args: |
             CARGO_NET_GIT_FETCH_WITH_CLI=true
+
+      - name: Sign the images with GitHub OIDC Token
+        env:
+          DIGEST: ${{ steps.build-and-push.outputs.digest }}
+          TAGS: ${{ steps.set-tag.outputs.tags }}
+        run: |
+          images=""
+          for tag in ${TAGS}; do
+            images+="${tag}@${DIGEST} "
+          done
+          cosign sign --yes ${images}

.github/workflows/docs-pr-netlify.yaml

+name: Deploy documentation PR preview
+
+on:
+  workflow_run:
+    workflows: [ "Prepare documentation PR preview" ]
+    types:
+      - completed
+
+jobs:
+  netlify:
+    if: github.event.workflow_run.conclusion == 'success' && github.event.workflow_run.event == 'pull_request'
+    runs-on: ubuntu-latest
+    steps:
+      # There's a 'download artifact' action, but it hasn't been updated for the workflow_run action
+      # (https://github.com/actions/download-artifact/issues/60) so instead we get this mess:
+      - name: 📥 Download artifact
+        uses: dawidd6/action-download-artifact@20319c5641d495c8a52e688b7dc5fada6c3a9fbc # v8
+        with:
+          workflow: docs-pr.yaml
+          run_id: ${{ github.event.workflow_run.id }}
+          name: book
+          path: book
+
+      - name: 📤 Deploy to Netlify
+        uses: matrix-org/netlify-pr-preview@v3
+        with:
+          path: book
+          owner: ${{ github.event.workflow_run.head_repository.owner.login }}
+          branch: ${{ github.event.workflow_run.head_branch }}
+          revision: ${{ github.event.workflow_run.head_sha }}
+          token: ${{ secrets.NETLIFY_AUTH_TOKEN }}
+          site_id: ${{ secrets.NETLIFY_SITE_ID }}
+          desc: Documentation preview
+          deployment_env: PR Documentation Preview