IFEM phase · interfaces
Interfaces — IFEM Doctrine
Interfaces describe the observable surface between responsibilities: what crosses the boundary, what is owned on each side, and what must remain private.
Purpose
The purpose is to reduce accidental coupling and give independent contributors a small, legible boundary they can implement and test.
Inputs and responsibilities
Inputs come from the architecture’s responsibility map, dependency decisions, data ownership, and the behavior that other responsibilities must observe.
Outputs and artifacts
An interface record identifies operations, data shapes, lifecycle expectations, ownership, compatibility concerns, and explicit non-goals.
Verification and decision gate
Verification tests whether the interface is sufficient for the next responsibility without leaking internal details or leaving acceptance behavior ambiguous.
Common failure modes
A broad convenience surface exposes internals, or a seemingly small omission forces consumers to coordinate through undocumented assumptions.
Execution notes
A dependable interface is deliberately smaller than the implementation behind it. It gives consumers a stable vocabulary while allowing the owner to change internal representation. Dependency direction should follow the responsibility agreement, and ownership should be clear for data, errors, and lifecycle decisions. When these details are explicit, the next Contracts phase can turn the boundary into a versioned agreement instead of reconstructing it from usage.