atdd

Acceptance test driven development is enforced by writing feature behavior in Gherkin before implementation. The system generates executable acceptance tests from a portable spec IR, binds step handlers to internals, and runs tests until both acceptance and unit streams pass.

AI-assisted coding drifts when implementation lacks locked specifications. Starting with domain-language Gherkin specs prevents drift by constraining external behavior and internal correctness through dual-stream acceptance and unit test validation.

Prevent spec drift by applying permission-gated edits to spec.md and enforcing regeneration discipline. The workflow regenerates executable pipelines from the original spec and traces failures back to the source scenario to maintain spec integrity.

Dual-stream verification generates and runs acceptance tests alongside unit tests. This parallel validation ensures the system's external behavior and internal structure are both constrained throughout the test-driven iteration cycle.

Acceptance-first discipline requires writing spec.md in domain language before implementation. This spec-first planning locks in what done means, generates the test pipeline, and drives TDD iteration until both test streams pass.

Step handlers bind to real internals after generating executable acceptance tests from the portable spec IR. This connects Gherkin scenarios to actual application logic, enabling traceability from test failures back to the source spec.