work-unit-commits

When to Use

Load this skill when deciding what belongs in each commit or PR.

Use it for:

• Splitting a feature into reviewable work.
• Preparing commits before opening a PR.
• Turning a large change into chained or stacked PRs.
• Keeping reviewer cognitive load healthy.
• Applying SDD tasks without accidentally producing a PR above 400 changed lines.

Critical Rules

Rule	Requirement
Commit by work unit	A commit represents a deliverable behavior, fix, migration, or docs unit.
Do not commit by file type	Avoid models, then services, then tests if none works alone.
Keep tests with code	Tests belong in the same commit as the behavior they verify.
Keep docs with the user-visible change	Docs belong with the feature or workflow they explain.
Tell a story	A reviewer should understand why each commit exists from its diff and message.
Future PR-ready	Each commit should be a candidate chained PR when the change grows.
SDD workload guard	If SDD tasks forecast a >400-line change, group commits into chained PR slices before implementation.

Work Unit Checklist

Before committing, confirm:

• The commit has one clear purpose.
• The repo still makes sense after applying only this commit.
• Tests or docs for this unit are included when relevant.
• Rollback is reasonable without reverting unrelated work.
• Focused test command and exact result are recorded.
• Runtime harness command/scenario and exact result are recorded, or explicit N/A explains why no runtime boundary exists.
• Rollback boundary names the exact files/behavior removable without unrelated work.
• The commit message explains the outcome, not the file list.

Split Examples

Weak split	Better work-unit split
add models	feat(auth): add token validation domain model and tests
add services	feat(auth): wire token validation into login flow
add tests	Tests included with each behavior commit
update docs	Docs included with the user-facing change they explain

PR Relationship

Use work-unit commits as the foundation for chained PRs:

1. Build the smallest independent work unit.
2. Include verification for that unit.
3. Commit it with a Conventional Commit message.
4. If the PR approaches 400 changed lines, promote commits or groups of commits into chained PRs.

SDD Relationship

When sdd-tasks produces a Review Workload Forecast:

• Low risk: keep work-unit commits inside one PR.
• Medium risk: commit by work unit and monitor changed lines before PR creation.
• High risk: follow SDD delivery_strategy — ask on ask-on-risk, auto-slice on auto-chain, require size:exception on over-budget single-pr, or record accepted size:exception on exception-ok.
• Count authored additions plus deletions for the >400 threshold. Exclude generated goldens from that authored count, but include every generated file in complete snapshot identity and receipt validation.

Each SDD work unit should map cleanly to a commit or PR with:

• clear start state,
• clear finished state,
• verification in the same unit,
• rollback that does not remove unrelated work.

Its implementation evidence MUST include:

• Focused test command and exact result.
• Runtime harness command/scenario and exact result, or explicit N/A with reason.
• Rollback boundary stated independently of commit creation; uncommitted work units still require it.
• When fixing a bounded review ledger, group atomic work units inside the single correction transaction; work-unit count never creates another fix budget.

Commands

# Review the story before committing
git diff --stat
git diff --cached --stat

# Check recent commit style
git log --oneline -5