The Interface Layer is the cross-cutting stratum that defines the boundaries and contracts through which components communicate. It sits above the integration and transport mechanisms that carry calls and below the applications that consume the contracts. It contains interface definitions, schemas, and the conventions that govern interaction.
Semantic Classification
Content
- The Interface Layer specifies the agreed boundaries across which parts of a system interact, independent of their internal implementation. Typical members include interface and schema definitions, versioning rules, and the conventions for compatibility and deprecation. It is concerned with contracts rather than the data path itself.
- It requires the API Layer for concrete endpoint definitions and the Integration Layer that connects parties to them. It enables the Application and Presentation Layers, which depend on stable contracts to build against. Clear interfaces let components evolve without breaking their consumers.
- The layer bridges to the interface segregation principle and the concept of a schema, which keep contracts cohesive and well-typed. Compatibility guarantees made here determine how disruptive change can be to dependants.