Changelog Automation

Patterns and tools for automating changelog generation, release notes, and version management following industry standards.

When to Use This Skill

• Setting up automated changelog generation
• Implementing Conventional Commits
• Creating release note workflows
• Standardizing commit message formats
• Generating GitHub/GitLab release notes
• Managing semantic versioning

Core Concepts

1. Keep a Changelog Format

# Changelog

All notable changes to this project will be documented in this file.

The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

## [Unreleased]

### Added
- New feature X

## [1.2.0] - 2024-01-15

### Added
- User profile avatars
- Dark mode support

### Changed
- Improved loading performance by 40%

### Deprecated
- Old authentication API (use v2)

### Removed
- Legacy payment gateway

### Fixed
- Login timeout issue (#123)

### Security
- Updated dependencies for CVE-2024-1234

[Unreleased]: https://github.com/user/repo/compare/v1.2.0...HEAD
[1.2.0]: https://github.com/user/repo/compare/v1.1.0...v1.2.0

2. Conventional Commits

<type>[optional scope]: <description>

[optional body]

[optional footer(s)]

Type	Description	Changelog Section
feat	New feature	Added
fix	Bug fix	Fixed
docs	Documentation	(usually excluded)
style	Formatting	(usually excluded)
refactor	Code restructure	Changed
perf	Performance	Changed
test	Tests	(usually excluded)
chore	Maintenance	(usually excluded)
ci	CI changes	(usually excluded)
build	Build system	(usually excluded)
revert	Revert commit	Removed

3. Semantic Versioning

MAJOR.MINOR.PATCH

MAJOR: Breaking changes (feat! or BREAKING CHANGE)
MINOR: New features (feat)
PATCH: Bug fixes (fix)

Implementation

Method 1: Conventional Changelog (Node.js)

# Install tools
npm install -D @commitlint/cli @commitlint/config-conventional
npm install -D husky
npm install -D standard-version
# or
npm install -D semantic-release

# Setup commitlint
cat > commitlint.config.js << 'EOF'
module.exports = {
  extends: ['@commitlint/config-conventional'],
  rules: {
    'type-enum': [
      2,
      'always',
      [
        'feat',
        'fix',
        'docs',
        'style',
        'refactor',
        'perf',
        'test',
        'chore',
        'ci',
        'build',
        'revert',
      ],
    ],
    'subject-case': [2, 'never', ['start-case', 'pascal-case', 'upper-case']],
    'subject-max-length': [2, 'always', 72],
  },
};
EOF

# Setup husky
npx husky init
echo "npx --no -- commitlint --edit \$1" > .husky/commit-msg

Method 2: standard-version Configuration

// .versionrc.js
module.exports = {
  types: [
    { type: 'feat', section: 'Features' },
    { type: 'fix', section: 'Bug Fixes' },
    { type: 'perf', section: 'Performance Improvements' },
    { type: 'revert', section: 'Reverts' },
    { type: 'docs', section: 'Documentation', hidden: true },
    { type: 'style', section: 'Styles', hidden: true },
    { type: 'chore', section: 'Miscellaneous', hidden: true },
    { type: 'refactor', section: 'Code Refactoring', hidden: true },
    { type: 'test', section: 'Tests', hidden: true },
    { type: 'build', section: 'Build System', hidden: true },
    { type: 'ci', section: 'CI/CD', hidden: true },
  ],
  commitUrlFormat: '{{host}}/{{owner}}/{{repository}}/commit/{{hash}}',
  compareUrlFormat: '{{host}}/{{owner}}/{{repository}}/compare/{{previousTag}}...{{currentTag}}',
  issueUrlFormat: '{{host}}/{{owner}}/{{repository}}/issues/{{id}}',
  userUrlFormat: '{{host}}/{{user}}',
  releaseCommitMessageFormat: 'chore(release): {{currentTag}}',
  scripts: {
    prebump: 'echo "Running prebump"',
    postbump: 'echo "Running postbump"',
    prechangelog: 'echo "Running prechangelog"',
    postchangelog: 'echo "Running postchangelog"',
  },
};

// package.json scripts
{
  "scripts": {
    "release": "standard-version",
    "release:minor": "standard-version --release-as minor",
    "release:major": "standard-version --release-as major",
    "release:patch": "standard-version --release-as patch",
    "release:dry": "standard-version --dry-run"
  }
}

Method 3: semantic-release (Full Automation)

// release.config.js
module.exports = {
  branches: [
    'main',
    { name: 'beta', prerelease: true },
    { name: 'alpha', prerelease: true },
  ],
  plugins: [
    '@semantic-release/commit-analyzer',
    '@semantic-release/release-notes-generator',
    [
      '@semantic-release/changelog',
      {
        changelogFile: 'CHANGELOG.md',
      },
    ],
    [
      '@semantic-release/npm',
      {
        npmPublish: true,
      },
    ],
    [
      '@semantic-release/github',
      {
        assets: ['dist/**/*.js', 'dist/**/*.css'],
      },
    ],
    [
      '@semantic-release/git',
      {
        assets: ['CHANGELOG.md', 'package.json'],
        message: 'chore(release): ${nextRelease.version} [skip ci]\n\n${nextRelease.notes}',
      },
    ],
  ],
};

Method 4: GitHub Actions Workflow

# .github/workflows/release.yml
name: Release

on:
  push:
    branches: [main]
  workflow_dispatch:
    inputs:
      release_type:
        description: 'Release type'
        required: true
        default: 'patch'
        type: choice
        options:
          - patch
          - minor
          - major

permissions:
  contents: write
  pull-requests: write

jobs:
  release:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
          token: ${{ secrets.GITHUB_TOKEN }}

      - uses: actions/setup-node@v4
        with:
          node-version: '20'
          cache: 'npm'

      - run: npm ci

      - name: Configure Git
        run: |
          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"

      - name: Run semantic-release
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
        run: npx semantic-release

  # Alternative: manual release with standard-version
  manual-release:
    if: github.event_name == 'workflow_dispatch'
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - uses: actions/setup-node@v4
        with:
          node-version: '20'

      - run: npm ci

      - name: Configure Git
        run: |
          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"

      - name: Bump version and generate changelog
        run: npx standard-version --release-as ${{ inputs.release_type }}

      - name: Push changes
        run: git push --follow-tags origin main

      - name: Create GitHub Release
        uses: softprops/action-gh-release@v1
        with:
          tag_name: ${{ steps.version.outputs.tag }}
          body_path: RELEASE_NOTES.md
          generate_release_notes: true

Method 5: git-cliff (Rust-based, Fast)

# cliff.toml
[changelog]
header = """
# Changelog

All notable changes to this project will be documented in this file.

"""
body = """
{% if version %}\
    ## [{{ version | trim_start_matches(pat="v") }}] - {{ timestamp | date(format="%Y-%m-%d") }}
{% else %}\
    ## [Unreleased]
{% endif %}\
{% for group, commits in commits | group_by(attribute="group") %}
    ### {{ group | upper_first }}
    {% for commit in commits %}
        - {% if commit.scope %}**{{ commit.scope }}:** {% endif %}\
            {{ commit.message | upper_first }}\
            {% if commit.github.pr_number %} ([#{{ commit.github.pr_number }}](https://github.com/owner/repo/pull/{{ commit.github.pr_number }})){% endif %}\
    {% endfor %}
{% endfor %}
"""
footer = """
{% for release in releases -%}
    {% if release.version -%}
        {% if release.previous.version -%}
            [{{ release.version | trim_start_matches(pat="v") }}]: \
                https://github.com/owner/repo/compare/{{ release.previous.version }}...{{ release.version }}
        {% endif -%}
    {% else -%}
        [unreleased]: https://github.com/owner/repo/compare/{{ release.previous.version }}...HEAD
    {% endif -%}
{% endfor %}
"""
trim = true

[git]
conventional_commits = true
filter_unconventional = true
split_commits = false
commit_parsers = [
    { message = "^feat", group = "Features" },
    { message = "^fix", group = "Bug Fixes" },
    { message = "^doc", group = "Documentation" },
    { message = "^perf", group = "Performance" },
    { message = "^refactor", group = "Refactoring" },
    { message = "^style", group = "Styling" },
    { message = "^test", group = "Testing" },
    { message = "^chore\\(release\\)", skip = true },
    { message = "^chore", group = "Miscellaneous" },
]
filter_commits = false
tag_pattern = "v[0-9]*"
skip_tags = ""
ignore_tags = ""
topo_order = false
sort_commits = "oldest"

[github]
owner = "owner"
repo = "repo"

# Generate changelog
git cliff -o CHANGELOG.md

# Generate for specific range
git cliff v1.0.0..v2.0.0 -o RELEASE_NOTES.md

# Preview without writing
git cliff --unreleased --dry-run

Method 6: Python (commitizen)

# pyproject.toml
[tool.commitizen]
name = "cz_conventional_commits"
version = "1.0.0"
version_files = [
    "pyproject.toml:version",
    "src/__init__.py:__version__",
]
tag_format = "v$version"
update_changelog_on_bump = true
changelog_incremental = true
changelog_start_rev = "v0.1.0"

[tool.commitizen.customize]
message_template = "{{change_type}}{% if scope %}({{scope}}){% endif %}: {{message}}"
schema = "<type>(<scope>): <subject>"
schema_pattern = "^(feat|fix|docs|style|refactor|perf|test|chore)(\\(\\w+\\))?:\\s.*"
bump_pattern = "^(feat|fix|perf|refactor)"
bump_map = {"feat" = "MINOR", "fix" = "PATCH", "perf" = "PATCH", "refactor" = "PATCH"}

# Install
pip install commitizen

# Create commit interactively
cz commit

# Bump version and update changelog
cz bump --changelog

# Check commits
cz check --rev-range HEAD~5..HEAD

Release Notes Templates

GitHub Release Template

## What's Changed

### 🚀 Features
{{ range .Features }}
- {{ .Title }} by @{{ .Author }} in #{{ .PR }}
{{ end }}

### 🐛 Bug Fixes
{{ range .Fixes }}
- {{ .Title }} by @{{ .Author }} in #{{ .PR }}
{{ end }}

### 📚 Documentation
{{ range .Docs }}
- {{ .Title }} by @{{ .Author }} in #{{ .PR }}
{{ end }}

### 🔧 Maintenance
{{ range .Chores }}
- {{ .Title }} by @{{ .Author }} in #{{ .PR }}
{{ end }}

## New Contributors
{{ range .NewContributors }}
- @{{ .Username }} made their first contribution in #{{ .PR }}
{{ end }}

**Full Changelog**: https://github.com/owner/repo/compare/v{{ .Previous }}...v{{ .Current }}

Internal Release Notes

# Release v2.1.0 - January 15, 2024

## Summary
This release introduces dark mode support and improves checkout performance
by 40%. It also includes important security updates.

## Highlights

### 🌙 Dark Mode
Users can now switch to dark mode from settings. The preference is
automatically saved and synced across devices.

### ⚡ Performance
- Checkout flow is 40% faster
- Reduced bundle size by 15%

## Breaking Changes
None in this release.

## Upgrade Guide
No special steps required. Standard deployment process applies.

## Known Issues
- Dark mode may flicker on initial load (fix scheduled for v2.1.1)

## Dependencies Updated
| Package | From | To | Reason |
|---------|------|-----|--------|
| react | 18.2.0 | 18.3.0 | Performance improvements |
| lodash | 4.17.20 | 4.17.21 | Security patch |

Commit Message Examples

# Feature with scope
feat(auth): add OAuth2 support for Google login

# Bug fix with issue reference
fix(checkout): resolve race condition in payment processing

Closes #123

# Breaking change
feat(api)!: change user endpoint response format

BREAKING CHANGE: The user endpoint now returns `userId` instead of `id`.
Migration guide: Update all API consumers to use the new field name.

# Multiple paragraphs
fix(database): handle connection timeouts gracefully

Previously, connection timeouts would cause the entire request to fail
without retry. This change implements exponential backoff with up to
3 retries before failing.

The timeout threshold has been increased from 5s to 10s based on p99
latency analysis.

Fixes #456
Reviewed-by: @alice

Best Practices

Do's

• Follow Conventional Commits - Enables automation
• Write clear messages - Future you will thank you
• Reference issues - Link commits to tickets
• Use scopes consistently - Define team conventions
• Automate releases - Reduce manual errors

Don'ts

• Don't mix changes - One logical change per commit
• Don't skip validation - Use commitlint
• Don't manual edit - Generated changelogs only
• Don't forget breaking changes - Mark with ! or footer
• Don't ignore CI - Validate commits in pipeline

Resources

• Keep a Changelog
• Conventional Commits
• Semantic Versioning
• semantic-release
• git-cliff