typespec-cross-layer

TypeSpec cross-layer mapping applies default inferences and override decorators to emit Postgres DDL, Kotlin data classes, and TypeScript types from a single model definition. You define your TypeSpec model and run the appropriate emitters to generate multi-target outputs.

Yes, TypeSpec type mapping supports override decorators for non-default mappings. Default inferences handle standard conversions to Postgres, Kotlin, and TypeScript, while explicit overrides allow granular control when default behavior does not match target system requirements.

Patch semantics in TypeSpec cross-layer mapping treat fields as optional and nullable to support partial updates. The system separates input and output types per HTTP method, ensuring patch operations correctly distinguish between omitted fields and explicit null values.

Yes, the mapping generates separate input and output types per HTTP method. This separation ensures that request bodies and response payloads have distinct type structures, supporting session context injection where needed for bespoke systems.

TypeSpec cross-layer emitters produce Postgres DDL directly from your TypeSpec models using default type inferences. For non-standard column types or constraints, apply override decorators before running the DDL emitter to ensure accurate schema generation.

Use explicit TypeSpec override decorators when target systems require non-default type mappings, such as bespoke storage formats or language-specific types that default inferences cannot predict. Default mappings cover standard Postgres, Kotlin, and TypeScript conversions safely.