diff --git a/.github/workflows/checks.yml b/.github/workflows/checks.yml
index 843134f..4d6b5a9 100644
--- a/.github/workflows/checks.yml
+++ b/.github/workflows/checks.yml
@@ -1,48 +1,50 @@
+---
 name: Checks
 
 on:
-  push:
-    branches:
-      - master
-  pull_request:
-    branches:
-      - master
+    push:
+        branches:
+            - master
+    pull_request:
+        branches:
+            - master
 
 jobs:
-  build:
+    build:
+        runs-on: ubuntu-latest
 
-    runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        include:
-        - python-version: "3.13"  # Keep in sync with .readthedocs.yml
-          env:
-            TOXENV: docs
-        - python-version: "3.13"
-          env:
-            TOXENV: pre-commit
-        - python-version: "3.13"
-          env:
-            TOXENV: pylint
-        - python-version: "3.13"
-          env:
-            TOXENV: typing
-        - python-version: "3.13"
-          env:
-            TOXENV: twinecheck
+        strategy:
+            fail-fast: false
+            matrix:
+                include:
+                    # Keep in sync with .readthedocs.yml
+                    - python-version: '3.13'
+                      env:
+                          TOXENV: docs
+                    - python-version: '3.13'
+                      env:
+                          TOXENV: pre-commit
+                    - python-version: '3.13'
+                      env:
+                          TOXENV: pylint
+                    - python-version: '3.13'
+                      env:
+                          TOXENV: typing
+                    - python-version: '3.13'
+                      env:
+                          TOXENV: twinecheck
 
-    steps:
-    - uses: actions/checkout@v4
+        steps:
+            - uses: actions/checkout@v4
 
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v5
-      with:
-        python-version: ${{ matrix.python-version }}
+            - name: Set up Python ${{ matrix.python-version }}
+              uses: actions/setup-python@v5
+              with:
+                  python-version: ${{ matrix.python-version }}
 
-    - name: Run check
-      env: ${{ matrix.env }}
-      run: |
-        pip install --upgrade pip
-        pip install --upgrade tox
-        tox
+            - name: Run check
+              env: ${{ matrix.env }}
+              run: |
+                  pip install --upgrade pip
+                  pip install --upgrade tox
+                  tox
diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
index f6e80b9..5cb1ffb 100644
--- a/.github/workflows/publish.yml
+++ b/.github/workflows/publish.yml
@@ -1,34 +1,36 @@
+---
 name: Publish
 
 on:
-  push:
-    tags:
-      - v*
+    push:
+        tags:
+            - v*
 
 jobs:
-  publish:
-    runs-on: ubuntu-latest
+    publish:
+        runs-on: ubuntu-latest
 
-    steps:
-    - uses: actions/checkout@v4
+        steps:
+            - uses: actions/checkout@v4
 
-    - name: Set up Python 3.13
-      uses: actions/setup-python@v5
-      with:
-        python-version: 3.13
+            - name: Set up Python 3.13
+              uses: actions/setup-python@v5
+              with:
+                  python-version: '3.13'
 
-    - name: Check Tag
-      id: check-release-tag
-      run: |
-        if [[ ${{ github.event.ref }} =~ ^refs/tags/v[0-9]+[.][0-9]+[.][0-9]+(rc[0-9]+|[.]dev[0-9]+)?$ ]]; then
-          echo ::set-output name=release_tag::true
-        fi
+            - name: Check Tag
+              id: check-release-tag
+              run: |
+                  RE="^refs/tags/v[0-9]+[.][0-9]+[.][0-9]+(rc[0-9]+|[.]dev[0-9]+)?$"
+                  if [[ ${{ github.event.ref }} =~ $RE ]]; then
+                    echo ::set-output name=release_tag::true
+                  fi
 
-    - name: Publish to PyPI
-      if: steps.check-release-tag.outputs.release_tag == 'true'
-      run: |
-        pip install --upgrade build twine
-        python -m build
-        export TWINE_USERNAME=__token__
-        export TWINE_PASSWORD=${{ secrets.PYPI_TOKEN }}
-        twine upload dist/*
+            - name: Publish to PyPI
+              if: steps.check-release-tag.outputs.release_tag == 'true'
+              run: |
+                  pip install --upgrade build twine
+                  python -m build
+                  export TWINE_USERNAME=__token__
+                  export TWINE_PASSWORD=${{ secrets.PYPI_TOKEN }}
+                  twine upload dist/*
diff --git a/.github/workflows/tests-macos.yml b/.github/workflows/tests-macos.yml
index 30fe097..6682858 100644
--- a/.github/workflows/tests-macos.yml
+++ b/.github/workflows/tests-macos.yml
@@ -1,35 +1,44 @@
+---
 name: macOS
 
 on:
-  push:
-    branches:
-      - master
-  pull_request:
-    branches:
-      - master
+    push:
+        branches:
+            - master
+    pull_request:
+        branches:
+            - master
 
 jobs:
-  tests:
+    tests:
+        runs-on: macos-latest
 
-    runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13", "3.14.0-rc.1"]
+        strategy:
+            fail-fast: false
+            matrix:
+                python-version:
+                    - '3.9'
+                    - '3.10'
+                    - '3.11'
+                    - '3.12'
+                    - '3.13'
+                    - 3.14.0-rc.1
+                    - pypy3.10
+                    - pypy3.11
 
-    steps:
-    - uses: actions/checkout@v4
+        steps:
+            - uses: actions/checkout@v4
 
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v5
-      with:
-        python-version: ${{ matrix.python-version }}
+            - name: Set up Python ${{ matrix.python-version }}
+              uses: actions/setup-python@v5
+              with:
+                  python-version: ${{ matrix.python-version }}
 
-    - name: Run tests
-      run: |
-        pip install --upgrade pip
-        pip install --upgrade tox
-        tox -e py
+            - name: Run tests
+              run: |
+                  pip install --upgrade pip
+                  pip install --upgrade tox
+                  tox -e py
 
-    - name: Upload coverage report
-      uses: codecov/codecov-action@v5
+            - name: Upload coverage report
+              uses: codecov/codecov-action@v5
diff --git a/.github/workflows/tests-ubuntu.yml b/.github/workflows/tests-ubuntu.yml
index 2358254..7f05f94 100644
--- a/.github/workflows/tests-ubuntu.yml
+++ b/.github/workflows/tests-ubuntu.yml
@@ -1,35 +1,44 @@
+---
 name: Ubuntu
 
 on:
-  push:
-    branches:
-      - master
-  pull_request:
-    branches:
-      - master
+    push:
+        branches:
+            - master
+    pull_request:
+        branches:
+            - master
 
 jobs:
-  tests:
+    tests:
+        runs-on: ubuntu-latest
 
-    runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13", "3.14.0-rc.1", "pypy3.10", "pypy3.11"]
+        strategy:
+            fail-fast: false
+            matrix:
+                python-version:
+                    - '3.9'
+                    - '3.10'
+                    - '3.11'
+                    - '3.12'
+                    - '3.13'
+                    - 3.14.0-rc.1
+                    - pypy3.10
+                    - pypy3.11
 
-    steps:
-    - uses: actions/checkout@v4
+        steps:
+            - uses: actions/checkout@v4
 
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v5
-      with:
-        python-version: ${{ matrix.python-version }}
+            - name: Set up Python ${{ matrix.python-version }}
+              uses: actions/setup-python@v5
+              with:
+                  python-version: ${{ matrix.python-version }}
 
-    - name: Run tests
-      run: |
-        pip install --upgrade pip
-        pip install --upgrade tox
-        tox -e py
+            - name: Run tests
+              run: |
+                  pip install --upgrade pip
+                  pip install --upgrade tox
+                  tox -e py
 
-    - name: Upload coverage report
-      uses: codecov/codecov-action@v5
+            - name: Upload coverage report
+              uses: codecov/codecov-action@v5
diff --git a/.github/workflows/tests-windows.yml b/.github/workflows/tests-windows.yml
index 9087e72..c846e54 100644
--- a/.github/workflows/tests-windows.yml
+++ b/.github/workflows/tests-windows.yml
@@ -1,35 +1,44 @@
+---
 name: Windows
 
 on:
-  push:
-    branches:
-      - master
-  pull_request:
-    branches:
-      - master
+    push:
+        branches:
+            - master
+    pull_request:
+        branches:
+            - master
 
 jobs:
-  tests:
+    tests:
+        runs-on: windows-latest
 
-    runs-on: windows-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13", "3.14.0-rc.1"]
+        strategy:
+            fail-fast: false
+            matrix:
+                python-version:
+                    - '3.9'
+                    - '3.10'
+                    - '3.11'
+                    - '3.12'
+                    - '3.13'
+                    - 3.14.0-rc.1
+                    - pypy3.10
+                    - pypy3.11
 
-    steps:
-    - uses: actions/checkout@v4
+        steps:
+            - uses: actions/checkout@v4
 
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v5
-      with:
-        python-version: ${{ matrix.python-version }}
+            - name: Set up Python ${{ matrix.python-version }}
+              uses: actions/setup-python@v5
+              with:
+                  python-version: ${{ matrix.python-version }}
 
-    - name: Run tests
-      run: |
-        pip install --upgrade pip
-        pip install --upgrade tox
-        tox -e py
+            - name: Run tests
+              run: |
+                  pip install --upgrade pip
+                  pip install --upgrade tox
+                  tox -e py
 
-    - name: Upload coverage report
-      uses: codecov/codecov-action@v5
+            - name: Upload coverage report
+              uses: codecov/codecov-action@v5
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 119b328..7c59a32 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -1,22 +1,32 @@
+---
 repos:
-- repo: https://github.com/astral-sh/ruff-pre-commit
-  rev: v0.12.5
-  hooks:
-    - id: ruff-check
-      args: [ --fix ]
-    - id: ruff-format
-- repo: https://github.com/adamchainz/blacken-docs
-  rev: 1.19.1
-  hooks:
-  - id: blacken-docs
-    additional_dependencies:
-    - black==25.1.0
-- repo: https://github.com/pre-commit/pre-commit-hooks
-  rev: v5.0.0
-  hooks:
-  - id: end-of-file-fixer
-  - id: trailing-whitespace
-- repo: https://github.com/sphinx-contrib/sphinx-lint
-  rev: v1.0.0
-  hooks:
-    - id: sphinx-lint
+    - repo: https://github.com/astral-sh/ruff-pre-commit
+      rev: v0.12.5
+      hooks:
+          - id: ruff-check
+            args: [--fix]
+          - id: ruff-format
+    - repo: https://github.com/adamchainz/blacken-docs
+      rev: 1.19.1
+      hooks:
+          - id: blacken-docs
+            additional_dependencies:
+                - black==25.1.0
+    - repo: https://github.com/pre-commit/pre-commit-hooks
+      rev: v5.0.0
+      hooks:
+          - id: end-of-file-fixer
+          - id: trailing-whitespace
+    - repo: https://github.com/sphinx-contrib/sphinx-lint
+      rev: v1.0.0
+      hooks:
+          - id: sphinx-lint
+    - repo: https://github.com/adrienverge/yamllint.git
+      rev: v1.37.1
+      hooks:
+          - id: yamllint
+            args: [--format, parsable, --strict, -d, '{rules: {truthy: {check-keys: false}}}']
+    - repo: https://github.com/jumanjihouse/pre-commit-hook-yamlfmt
+      rev: 0.2.3
+      hooks:
+          - id: yamlfmt
diff --git a/.readthedocs.yml b/.readthedocs.yml
index 2b53eb1..a9c62c2 100644
--- a/.readthedocs.yml
+++ b/.readthedocs.yml
@@ -1,15 +1,16 @@
+---
 version: 2
 formats: all
 sphinx:
-  configuration: docs/conf.py
-  fail_on_warning: true
+    configuration: docs/conf.py
+    fail_on_warning: true
 build:
-  os: ubuntu-24.04
-  tools:
-    # For available versions, see:
-    # https://docs.readthedocs.io/en/stable/config-file/v2.html#build-tools-python
-    python: "3.13"  # Keep in sync with .github/workflows/build.yml
+    os: ubuntu-24.04
+    tools:
+        # For available versions, see:
+        # https://docs.readthedocs.io/en/stable/config-file/v2.html#build-tools-python
+        python: '3.13'  # Keep in sync with .github/workflows/build.yml
 python:
-  install:
-    - requirements: docs/requirements.txt
-    - path: .
+    install:
+        - requirements: docs/requirements.txt
+        - path: .
diff --git a/codecov.yml b/codecov.yml
index d8aa6b9..c8661fb 100644
--- a/codecov.yml
+++ b/codecov.yml
@@ -1,6 +1,7 @@
+---
 comment:
-  layout: "header, diff, tree"
+    layout: header, diff, tree
 
 coverage:
-  status:
-    project: false
+    status:
+        project: false