Checkpoint-Aware Implementation

You implement features methodically with user checkpoints between phases.

When to Activate

• •After the spec skill has created and confirmed a specification
• •When user says "implement" and a spec file exists
• •When user explicitly references a spec file

Workflow

1. Load Spec

Read the relevant /specs/{feature}.md file. If multiple specs exist and it's unclear which one, ask the user.

2. Create Task Breakdown

Use TodoWrite to break the spec into phases. Prefer this order when applicable:

1. •Foundation: Data models, types, schemas
2. •Core Logic: Business logic, algorithms, services
3. •Integration: Connect components, wire up UI
4. •Polish: Error handling, edge cases, validation
5. •Verification: Test against acceptance criteria

Adapt phases to the specific feature - not all features need all phases.

3. Execute with Checkpoints

For each phase:

1. •Announce what you're starting
2. •Implement the phase
3. •Summarize what was done (files changed, key decisions)
4. •Ask: "Phase complete. Ready for the next phase?"
5. •Only proceed on confirmation

This gives the user control to:

• •Review changes before continuing
• •Request adjustments
• •Pause and resume later

4. Verify Against Spec

Before marking the feature complete:

1. •Re-read the spec's acceptance criteria
2. •Check each criterion explicitly
3. •Report: "✓ Criterion met" or "⚠ Needs attention: {issue}"

Only mark complete when all criteria pass.

5. Update Spec

After successful implementation:

• •Update status to implemented: If the spec has front-matter with a status field, update it from proposed to implemented
• •Check off completed acceptance criteria in the spec file
• •Add any notes about implementation decisions

Checkpoint Behavior

Do checkpoint after:

• •Completing a logical phase
• •Making architectural decisions
• •Any change that affects multiple files

Skip checkpoint for:

• •Minor follow-up fixes within a phase
• •Formatting/cleanup
• •When user explicitly says "continue without asking"

Recovery

If implementation is interrupted:

• •TodoWrite preserves progress
• •Spec file shows which criteria are done
• •User can say "continue implementing {feature}" to resume