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name: waterfall-development description: Enforces strict waterfall development workflow with phase gates. Use when (1) features.yml exists in project root, (2) user asks to implement/develop/build a feature, (3) user explicitly requests waterfall workflow. Creates features.yml if missing when invoked.

Waterfall Development

Strict phase gate enforcement for waterfall workflow. Requires the feature-file skill for artifact management.

Phases

Requirements → Design → Implementation → Testing → Complete

Activation

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.

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

Gate failures print terse errors. No bypass mechanism.