step 5

docs/PHASE_6_BACKGROUND_PERSISTENCE_DESIGN.md

@@ -7,8 +7,8 @@ Phases 1-5 separate durable state, coordination policy, render-facing snapshots,
 ## Status
 
 - Phase 6 design package: proposed.
-- Phase 6 implementation: Step 4 complete.
-- Current alignment: `RuntimeStore` owns durable serialization, config, package metadata, preset IO, and persistence requests; `CommittedLiveState` owns the current committed/session layer state; and `RuntimeCoordinator` publishes typed persistence requests for persisted mutations. The remaining issue is that actual disk writes are still synchronous store work rather than queued, debounced, atomic background writes.
+- Phase 6 implementation: Step 5 complete.
+- Current alignment: `RuntimeStore` owns durable serialization, config, package metadata, preset IO, and persistence request execution; `CommittedLiveState` owns the current committed/session layer state; and `RuntimeCoordinator` publishes typed persistence requests for persisted mutations. Runtime-state persistence is now requested through the coordinator/event path and executed by the background writer.
 
 Current persistence footholds:
 
@@ -252,9 +252,17 @@ Route `RuntimePersistenceRequested` or coordinator persistence outcomes into the
 
 Initial target:
 
-- accepted durable mutations request persistence
-- transient-only mutations do not
-- runtime reload/preset policies remain explicit
+- [x] accepted durable mutations request persistence
+- [x] transient-only mutations do not
+- [x] runtime reload/preset policies remain explicit
+
+Current implementation:
+
+- Store mutation methods update committed durable/session state and mark render state dirty, but no longer enqueue runtime-state writes directly.
+- `RuntimeCoordinator` remains the owner of the persistence decision and publishes `RuntimePersistenceRequested` only for accepted durable mutations.
+- `RuntimeUpdateController` handles `RuntimePersistenceRequested` and calls `RuntimeStore::RequestPersistence(...)`.
+- `RuntimeStore::RequestPersistence(...)` validates the request target, builds the runtime-state snapshot, enqueues it on `PersistenceWriter`, and records enqueue failures in `HealthTelemetry`.
+- Stack preset save remains a synchronous preset-file write; preset load updates state and relies on the coordinator persistence request for runtime-state persistence.
 
 ### Step 6. Define Shutdown Flush
 
@@ -307,14 +315,14 @@ Operator-triggered preset save often feels like it should complete before report
 
 Phase 6 can be considered complete once the project can say:
 
-- [ ] durable mutations enqueue persistence instead of directly writing from mutation paths
-- [ ] runtime-state writes are debounced/coalesced
-- [ ] writes use temp-file/replace or equivalent atomic policy
-- [ ] persistence failures are reported through structured health/events
-- [ ] transient/live-only mutations do not request persistence
+- [x] durable mutations enqueue persistence instead of directly writing from mutation paths
+- [x] runtime-state writes are debounced/coalesced
+- [x] writes use temp-file/replace or equivalent atomic policy
+- [x] persistence failures are reported through structured health/events
+- [x] transient/live-only mutations do not request persistence
 - [ ] shutdown flush behavior is explicit and tested
-- [ ] `RuntimeStore` remains durable-state/serialization owner, not worker policy owner
-- [ ] persistence behavior has focused non-render tests
+- [x] `RuntimeStore` remains durable-state/serialization owner, not worker policy owner
+- [x] persistence behavior has focused non-render tests
 
 ## Open Questions