test-driven-development

Test-first workflow for PowerShell and DSC work: the red-green-refactor loop, writing a failing Pester 5 test before the code, the test pyramid (unit-heavy), DAMP-over-DRY test readability, choosing what and at which level to test, and making behaviour changes test-first rather than test-after. Enforces "no production change without a covering test" as a checkable gate. USE FOR: TDD, test-driven development, test first, red green refactor, write the test first, failing test before code, what should I test, test pyramid, unit vs integration test, coverage discipline, regression test for a bug, characterization test, DAMP tests, arrange act assert, testable design. DO NOT USE FOR: Pester recipes and mocking templates (use pester-patterns), diagnosing a failing build or test (use sampler-build-debug), Pester syntax (see pester.instructions.md), running tests without freezing VS Code (see powershell-execution-safety.instructions.md), evaluating skills/prompts/agents (use agent-evals).