incremental-tddlisted

# 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](references/deep-modules.md) – why deep modules make AI‑driven TDD easier and safer. - [refactoring.md](references/refactoring.md) – patterns for safe refactors. - [interface-design.md](assets/interface-design.md) – how to design interfaces for TDD. - [mocking.md](assets/mocking.md) – how and when to mock without lying to yourself. - [tests.md](assets/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: - Wants to build a feature or fix a bug **using TDD**. - Mentions “red‑green‑refactor”, “test‑first”, or “write the tests first”. - Wants honest integration or module‑level tests that drive design rather than brittle unit tests. - Is running longer “Ralph” loops or autonomous agents and wants higher‑quality changes. If the requirements are unclear, suggest using `/grill-me` and `/spec-writer` first, then come back here for execution. ## Overall Workflow You can compress steps when context is obvious, but keep the **red → gree