Test-Driven Development (Red-Green-Refactor)

This skill forces you to work in tight TDD loops: one failing test, one implementation, then refactor. It prefers vertical slices and deep modules so tests stay honest, stable, and focused on real behavior instead of implementation details.

This skill comes with extra documents you can reference for philosophy and examples:

• deep-modules.md – why deep modules make AI‑driven TDD easier and safer.
• refactoring.md – patterns for safe refactors.
• interface-design.md – how to design interfaces for TDD.
• mocking.md – how and when to mock without lying to yourself.
• tests.md – how and when to mock without lying to yourself.

When you need guidance on design or refactoring, open and read these files instead of guessing.

When to Use

Use this skill when the user: