---
name: commit
description: Commit procedure and message rules. Use for every commit.
---

# Commit

The procedure applies to normal repository commits, including code and
documentation commits. Each must use the configured signing key.
Internal git-bug commits for issues, comments, status changes, and other
tracker metadata are exempt from signing and may be unsigned. This
exception does not permit unsigned code or documentation commits.

## Procedure

1. Confirm that the configured signing key is available. If signing is
   unavailable or fails, stop and report the problem. Never disable
   signing, bypass it with a command or configuration override, or
   create an unsigned normal repository commit.
2. Do the `check` skill. All checks must pass before you commit.
3. Stage only the files that belong to this change. Keep unrelated
   changes in separate commits.
4. Write the complete message to a file, including all trailers. Add
   trailers with `git interpret-trailers --trailer` before the check,
   not after it. Never put `\n` in `git commit -m`.
5. Run `sh .githooks/commit-msg MESSAGE_FILE` on that final file before
   `git commit`. Fix every failure and run the check again. Sign with
   the configured key, using `git commit -S -F MESSAGE_FILE` on the same
   file. Do not add or change trailers after the check. The normal
   commit hook still runs. Never skip it with `--no-verify`.
6. Cryptographically verify each new normal commit's signature against
   the configured key before reporting completion. A signature header
   alone is not verification. If `gpg.ssh.allowedSignersFile` is not
   set, use a temporary allowed-signers file with the configured key. Do
   not change the Git configuration. If verification fails, stop and
   report it. Do not claim completion or publish the commit.

## Size

- Commit often. Split the work into small, coherent, working steps, and
  do not wait for a full feature.
- Use fixup commits for review corrections when the task requires them.
  Report the corrections and the pending fixups, but do not report the
  work as complete while `fixup!` or `squash!` commits remain.
- Before autosquashing, obtain the user's explicit approval to rewrite
  the affected commit range. Permission to create a fixup does not
  authorize a history rewrite. If approval is absent, stop and ask.
- After an approved autosquash, sign and verify each rewritten normal
  commit, rerun the required checks, and obtain independent review of
  the final range before reporting completion.
- Push code only with the user's authorization. A remote does not give
  permission to push.
- Rebase before an authorized push only when the task permits it. Do not
  rewrite published commits without the user's explicit approval. Stop
  and ask when an operation needs that approval. Never make a merge
  commit.

## Subject

- Use 50 characters or fewer.
- Write a short summary in the present-tense imperative mood.
- Capitalize the first word. Do not end with a period.
- Do not use a subsystem or prefix.

## Body

- Separate the subject from the body with exactly one blank line.
- Always write a body. Wrap each line at 72 characters. Fill each line
  of a paragraph before you wrap it. `bin/reflow` formats source
  comments at 80 columns, not commit prose. Do not use it to format a
  commit message.
- Write in the present-tense declarative mood.
- Start with a direct summary of the complete change. Do not only repeat
  the subject.
- Explain what the change does and why it is necessary. Describe the
  resulting behavior and design.
- Do not describe the development process, list the changed files, or
  give obvious implementation steps.

## Trailers

- When the change belongs to an issue, end the message with one `Issue:`
  trailer. Use the shortest unique git-bug issue ID in the `Issue:`
  trailer, with a minimum of seven characters. Check uniqueness against
  all issues, not only open issues. Assemble it with
  `git interpret-trailers --trailer` before the message check. Never use
  a closing keyword such as "Fixes" or "Closes".
- Link the bug report when a change fixes a reported bug.
- Include a stable archive URL when a change comes from a mailing-list
  or forum discussion.
- Do not add an AI tool as co-author. Do not add attribution trailers.

## Example

```
Print the program name

OneChat prints its name and exits. The program gives the Nix package a
binary that the install check can run, so the build pipeline is tested
before the first feature.
```