What problem does it solve? When migrating a legacy system to a new architecture, teams struggle to prove the new system behaves equivalently to the old one, especially when the migration involves a paradigm shift (e.g., synchronous to event-driven). This Skill defines the validation strategy and produces parity specifications that make equivalence testable. ## Core Features & Use Cases - Parity Strategy Definition: Selects validation modes (shadow mode, characterization tests, contract tests, data parity) and defines acceptance criteria such as divergence thresholds and observation windows. - Paradigm-Adapted Coverage: Adjusts required test dimensions based on the paradigm transition, adding idempotency, ordering, immutability, or supervision scenarios where needed. - Gherkin Spec Generation: Produces one .feature file per critical flow with traceability to legacy analysis artifacts, plus visual parity scenarios when screen modernization is involved. - Use Case: A team migrating a procedural monolith to an event-driven system uses this Skill to generate parity specs requiring @idempotencia and @ordem scenarios for every critical flow, with a divergence metric below 0.01% over 30 days as the cutover gate. ## Quick Start Invoke /reversa-inspector after the migration strategy and target architecture are approved to generate parity_specs.md and Gherkin parity test files under _reversa_sdd/migration/.
