edit-library-transformers

To build library-implemented transformers using TDD in TypeScript, follow an 8-step workflow: run pre-flight tests, define the transformer with transformerImplementationType set to libraryImplementation, implement the handler, and verify with devBuild and full test suites.

The workflow for wiring a Miroir transformer definition involves creating a TransformerDefinition JSON, implementing the TypeScript handler in TransformersForRuntime.ts, and registering it across runtime and build-time collections to ensure schema registration and type generation stay in sync.

To update an existing TypeScript transformer handler and keep schema and types in sync, edit the handler code in TransformersForRuntime.ts, update its runtime and build-time registrations, and execute devBuild to validate type generation and end-to-end functionality.

Yes, the Miroir transformer TDD workflow explicitly supports both in-memory and SQL-backed execution paths, ensuring consistent transformer registrations and TypeScript handler behavior across different runtime environments.

Yes, you can use this workflow to create a new transformer like formatDate by generating a new TransformerDefinition JSON, setting transformerImplementationType to libraryImplementation, and implementing the TypeScript handler before running the full test suite.

When editing TransformersForRuntime.ts for library-based transformers, limitations include the strict requirement to manually wire transformer registrations across runtime and build-time collections and the necessity of executing devBuild to ensure proper schema and type generation.