Guides stable API and interface design. Use when designing APIs, module boundaries, or any public interface. Use when creating REST or GraphQL endpoints, defining type contracts between modules, or establishing boundaries between frontend and backend.
Use when deciding where backend code should live in Iced Latte, especially feature ownership, `api/` boundaries, `common` vs feature placement, or cross-feature module dependencies in the modular monolith.
Use when adding or changing database schema, Liquibase changelogs, SQL migration files, rollout order, or schema-backed backend behavior in Iced Latte backend.
Use when backend changes risk crossing feature boundaries, changing exported `api/` surfaces, or violating Spring Modulith dependency expectations in Iced Latte.
Use when changing public backend API behavior, OpenAPI-owned request or response shapes, generated DTO boundaries, endpoint contracts, or compatibility rules in Iced Latte backend.
Use when changing backend JWT auth, sessions, Google OAuth, security filters, auth endpoints, authentication or authorization rules, or security-owned module boundaries in Iced Latte.
Use when choosing backend verification for changes that touch integration tests, PostgreSQL, Redis, Kafka, or any test flow that depends on Testcontainers in Iced Latte.
Guides systematic root-cause debugging. Use when tests fail, builds break, behavior doesn't match expectations, or you encounter any unexpected error. Use when you need a systematic approach to finding and fixing the root cause rather than guessing.