What problem does it solve? Writing tests for the Peajes Transformation Engine requires knowing which strategies, pipeline rules, and validation constraints (RN-16, RN-18, RN-20, RN-24) to cover, which fixtures to use, and which tooling (Karma/Jasmine, tsx, Supabase pgTAP) applies to each layer. This Skill provides the complete testing strategy, ground-truth data, and file layout so tests are deterministic and consistent. ## Core Features & Use Cases - Unit test patterns: Covers StrategyRegistry, PipelineBuilder, algorithm expanders, and column mapping with concrete I/O cases (e.g., 85557 → 08:55:57, 19.985,09 → 19985.09). - Integration and E2E guidance: Paso 3 wizard TestBed sketches, pipeline verification via tsx scripts, and invoice sum validation against Demo (102060.00) and Autopistas Urbanas (132940.19) fixtures. - Use Case: When adding a unit test for the COMBINAR_COLUMNAS strategy, use the documented Autopistas case (VAR + 02C → VAR-02C) and extend the existing motor.spec.ts instead of inventing new fixtures. ## Quick Start Ask the agent to write unit tests for the transformation strategies in motor.spec.ts using the Demo and Autopistas ground-truth fixtures.