What problem does it solve? Code written without tests leads to regressions, fragile refactors, and bugs reaching production. This Skill enforces a test-first workflow so every feature, bug fix, and refactor is backed by unit, integration, and E2E tests with at least 80% coverage. ## Core Features & Use Cases - Structured TDD Workflow: Guides the full red-green-refactor cycle from user journeys through failing tests, implementation, and coverage verification. - Test Patterns for Three Layers: Provides ready-to-use Jest/Vitest unit test patterns, Next.js API integration test patterns, and Playwright E2E test patterns. - Mocking and Coverage Guidance: Includes mocking templates for Supabase, Redis, and OpenAI plus Jest coverage threshold configuration. - Use Case: When adding a new API endpoint, the Skill walks you through writing failing integration tests first, implementing the route, then verifying coverage thresholds before committing. ## Quick Start Ask the AI to implement a new feature using the tdd-workflow skill so tests are written before any production code.