MaskingEngine

The serialization-neutral masking contract: given one field, decide what to write.

This is the seam every backend builds on. A backend calls decide per field — however it can reach one (Jackson wraps each property writer; a backend without a per-property hook may drive it during a tree rewrite or a custom encoder) — and executes the returned MaskingDecision. The engine holds all the value: policy resolution, per-call memoization, fail-closed behaviour, and the type contract. Recursion into nested resources and collection elements is the backend's concern, not the engine's.

Inheritors