| `RateLimiterStore` as interface (not concrete) | Interface only; `InMemoryRateLimiterStore` as default | Allows `cache-valkey` to satisfy it via duck typing without cross-module import |
| Fail-open rate limiting | Request allowed on store error | Availability preferred over hard enforcement during infrastructure degradation |
| `last_seen` excluded | Not in v1.0.0 | Application-domain concern; not transport-level middleware |
| UUID v7 for request IDs | v7 with v4 fallback | Time-ordered IDs sort chronologically in logs; fallback ensures generation never fails |
| `observability.Checkable` not redefined | Imported from contracts | Starters implement contracts directly; no web import needed by db/cache starters |
| Background goroutine for in-memory eviction | `time.Ticker` goroutine | Avoids `worker` module dependency; in-memory store is self-contained |
| `mw.RequestIDFrom` resolver sees the request (v1.4.0) | New entry point takes `func(*http.Request) string`; `RequestID` becomes a request-ignoring wrapper over it | An inbound correlation id must be able to survive this boundary, but acceptability is per-service — a typed audit column rejects what an opaque log accepts. The framework provides plumbing only (context + header, once per request); the app owns policy (which header, validation, generation fallback). An empty resolver result attaches nothing rather than a silently-empty value |
| `httputil` success status is configurable (v1.5.0) | `Handle`/`HandleNoBody`/`HandleEmpty` take `opts ...Option`; `WithStatus(code)` overrides the default (200 / 200 / 204) | 201 Created / 202 Accepted are common and were only reachable by hand-rolling the handler (losing decode+validate+error-mapping). Variadic options are non-breaking and future-extensible (headers, etc.). `WithStatus` is success-only (2xx) and panics at wiring on a non-2xx code — a wrong status is a routing mistake that should fail to boot, not surface at runtime; error status stays separate, resolved from the xerror by `Error` |