waterfall-developmentlisted

# Waterfall Development Strict phase gate enforcement for waterfall workflow. Requires the `feature-file` skill for artifact management. ## Phases Requirements → Design → Implementation → Testing → Complete ## Activation | Condition | Action | |-----------|--------| | features.yml exists | Activate, validate gates | | User invokes skill, no features.yml | Create features.yml via feature-file skill, then activate | | No features.yml, not invoked | Do not activate | ## Workflow 1. Run `./scripts/validate-gates.py` 2. If errors: Print errors, STOP 3. Identify target feature and current phase 4. Block work that doesn't match current phase 5. Before phase transitions: Re-validate target phase gates ## Gates See references/phase-gates.md for fix instructions. | Gate | Transition | Criteria | |------|------------|----------| | G1 | → Design | Feature has ≥1 requirement | | G2 | → Design | All requirements have descriptions | | G3 | → Implementation | decisions field exists | | G4 | → Testing | All requirements In-Progress or Complete | | G5 | → Complete | All requirements Complete + tested-by + all tests passing | ## Agent Usage Use sub-agents for verification tasks that require codebase exploration: **Before Design phase**: Verify requirements are complete by examining codebase and user request for implicit requirements. **Before Complete phase**: Verify test coverage by checking all requirements have corresponding tests and tested-by references. ## Error Handling G