Git Commit Standards

Commits tell the story of your codebase. A good commit history is worth more than any amount of documentation — because it's always up to date.

1. Conventional Commits Format

<type>(<scope>): <description>

[optional body]

[optional footer(s)]

Types:

Type	When
feat	New feature (correlates with MINOR in semver)
fix	Bug fix (correlates with PATCH in semver)
refactor	Code change that neither fixes a bug nor adds a feature
perf	Performance improvement
test	Adding or correcting tests
docs	Documentation changes only
chore	Build process, tooling, dependencies
ci	CI/CD configuration changes
style	Formatting, whitespace (not CSS — code formatting)

Scope:

Use the package name or module area:

feat(auth): add JWT refresh token rotation
fix(store/postgres): handle connection pool exhaustion
refactor(service): extract validation into dedicated package
test(handler): add table-driven tests for user endpoints
chore(deps): bump go.uber.org/zap to v1.27.0

Breaking changes:

feat(api)!: change pagination from offset to cursor-based

BREAKING CHANGE: The `offset` and `limit` query parameters are replaced
by `cursor` and `page_size`. All existing clients must migrate.

2. Commit Message Rules

Subject line:

• Imperative mood: "add feature", NOT "added feature" or "adds feature"
• Lowercase after type prefix
• No period at the end
• Max 72 characters
• Must describe WHAT changed, not HOW

Body (when needed):

• Blank line between subject and body
• Explain WHY the change was necessary
• Explain WHAT is different at a high level
• Wrap at 72 characters

Footer:

• Reference issues: Fixes #123, Closes #456, Refs #789
• Co-authors: Co-authored-by: Name <email>
• Breaking changes: BREAKING CHANGE: description

3. Examples

Simple change:

fix(handler): return 404 instead of 500 for missing user

With body:

refactor(service): replace manual SQL with sqlx named queries

The raw SQL string concatenation for dynamic WHERE clauses was
error-prone and difficult to maintain. sqlx named queries provide
the same flexibility with automatic parameter binding.

No behavior change — all existing tests pass.

Breaking change:

feat(config)!: migrate from YAML to environment variables

BREAKING CHANGE: Configuration is now loaded from environment
variables instead of config.yaml. See README.md for the full
list of supported variables.

Closes #234

Dependency update:

chore(deps): upgrade pgx to v5.5.0

Picks up connection pool improvements and fixes for
COPY protocol handling. See release notes:
https://github.com/jackc/pgx/releases/tag/v5.5.0

4. Atomic Commits

Each commit should be ONE logical change that:

• Compiles on its own (go build ./... passes)
• Tests pass (go test ./... passes)
• Can be reverted independently without breaking other changes

Split large changes:

# ❌ Bad — one commit doing everything
feat(user): add user management with CRUD, validation, auth, and tests

# ✅ Good — atomic, reviewable commits
feat(domain): add User entity and validation rules
feat(store): implement PostgreSQL user repository
feat(service): add user service with create and get operations
feat(handler): add REST endpoints for user management
test(service): add table-driven tests for user creation
docs(api): document user endpoints in OpenAPI spec

5. Pre-Commit Verification

Before committing, run:

# Format and lint
goimports -w .
golangci-lint run

# Build
go build ./...

# Test
go test -race ./...

# Tidy modules
go mod tidy

If any step fails, fix before committing. Never commit broken code with "will fix later" — you won't.

6. Commit Workflow

# Stage specific files (not git add .)
git add internal/service/user.go
git add internal/service/user_test.go

# Review staged changes
git diff --staged

# Commit with message
git commit -m "feat(service): add user creation with email validation"

# Or use editor for longer messages
git commit  # opens $EDITOR

Interactive rebase before PR:

# Clean up commit history before opening PR
git rebase -i main

# Squash fixup commits
# Reword unclear messages
# Reorder for logical flow

7. What NOT to Commit

• Generated files (*.pb.go unless required, mocks/)
• IDE configuration (.idea/, .vscode/ — use global gitignore)
• OS files (.DS_Store, Thumbs.db)
• Binaries and build artifacts
• .env files with secrets
• vendor/ (unless explicitly required by project policy)