Guided test-driven development workflow for .NET 10 using xUnit v3, WebApplicationFactory, Testcontainers, and Verify snapshots. Follows the strict red-green-refactor cycle. Use when: "TDD", "test-driven", "let's TDD this", "red green refactor", "write the test first", or when building a feature with clear acceptance criteria.

Use when implementing any feature or bugfix, before writing implementation code

Four-phase debugging framework that ensures root cause investigation before attempting fixes. Never jump to solutions.

Use when implementing any feature or bugfix, before writing implementation code

Use when facing 2+ independent tasks that can be worked on without shared state or sequential dependencies

Design comprehensive test cases using PICT (Pairwise Independent Combinatorial Testing) for any piece of requirements or code. Analyzes inputs, generates PICT models with parameters, values, and constraints for valid scenarios using pairwise testing. Outputs the PICT model, markdown table of test cases, and expected results.