This skill guides developers through the 'Outside-In' Test-Driven Development (TDD) methodology, prioritizing high-level acceptance tests that drive emergent design. By enforcing Hexagonal Architecture principles (Ports and Adapters), it helps teams defer infrastructure decisions, utilize high-fidelity in-memory fakes instead of brittle mocks, and maintain sub-second feedback loops. It is an essential companion for building complex backend services where maintainability, refactor-friendly code, and architectural purity are paramount.
主な機能
01Outer-loop acceptance testing to define system behavior at the boundary
02Five-step emergent design workflow: Inline, In-Memory, Interface, Deferred I/O
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04Strict Hexagonal Architecture enforcement with clear dependency rules
05Sub-second feedback testing strategy emphasizing component and acceptance tests
06Guidance on building 'Walking Skeletons' for new project integration
ユースケース
01Architecting a new microservice with a test-first, infrastructure-agnostic approach
02Refactoring tightly coupled legacy code into a clean Ports and Adapters structure
03Scaling complex business logic while maintaining a fast, reliable test suite