Commit Message Format

Commit message format defines the structure and content of git commit messages in a design system project. Well-formatted commit messages serve multiple purposes: they communicate changes to team members, enable automated tooling, and create a navigable project history. Establishing consistent formatting improves collaboration and supports release automation.

What Is Commit Message Format

Commit message format specifies how developers should structure and write their commit messages. This includes the message structure (subject, body, footer), content guidelines (what information to include), and style rules (tense, capitalization, length). Consistent formatting makes commit history readable and processable.

Most design system teams adopt or adapt established conventions like Conventional Commits. Custom formats may extend these conventions with project-specific requirements. The key is consistency that enables both human understanding and machine parsing.

How Commit Message Format Works

Effective commit message formats balance human readability with machine parseability. The format typically defines multiple sections serving different purposes.

The subject line provides a concise summary. It typically begins with a type prefix, optionally includes a scope, and concludes with a brief description. Length limits around 50-72 characters encourage concise summaries. The subject line appears in git log output and automated tools.

The optional body provides additional context. Separated from the subject by a blank line, the body can span multiple paragraphs explaining the motivation for changes, implementation approach, or implications. Not all commits need bodies, but complex changes benefit from explanation.

The optional footer contains metadata like breaking change notices, issue references, or co-author credits. Footer tokens follow specific formats that tools can parse. Breaking change footers trigger major version increments in automated versioning.

Key Considerations

• Subject lines should complete the phrase “this commit will…”
• Use imperative mood consistently throughout messages
• Reference issues and pull requests for traceability
• Breaking changes require explicit marking in the message
• Keep subject lines under 72 characters for readability

Common Questions

How should commit messages handle multiple changes?

Ideally, each commit represents a single logical change, making message formatting straightforward. When commits necessarily include multiple changes, the message should summarize the overall purpose rather than listing individual modifications.

If changes are truly unrelated, splitting into multiple commits improves history clarity. Squash merging allows clean history on the main branch while preserving detailed commits during development. The final squash commit message should follow format conventions.

For related changes that form a single logical unit, the subject line captures the high-level purpose while the body can detail individual modifications. Bullet points in the body help organize multiple related items.

How detailed should commit messages be?

Detail level should match change complexity and potential for confusion. Simple, obvious changes need only brief subject lines. Complex changes affecting multiple areas benefit from detailed body text explaining rationale and implications.

Consider the future audience. Developers investigating bugs, reviewers understanding changes, and release tools generating changelogs all use commit messages. Information helping these audiences belongs in commit messages.

Linking to issues, design documents, or discussions provides detail without bloating the message. A commit message can summarize while pointing to comprehensive documentation elsewhere. This approach balances commit history readability with information completeness.

Summary

Commit message format structures git history for human understanding and automated processing. Subject lines, bodies, and footers serve different purposes within consistent formatting rules. Effective formats balance detail with conciseness while supporting release automation and changelog generation.