- Every KV storage emits change events (base class owns writeMany/removeMany/ writeIfAbsent; implementations provide protected apply* methods) - KVStorageHttpServer streams changes over SSE (GET /events) with a resumable history; KVStorageHttp.watch() subscribes and resumes via Last-Event-ID - KVStorageIndexedDB for local persistence - KVStorageComposite keeps replicas of a source in sync: local reads, resume instead of full sync, offline outbox replayed in order, echo tracking - Values may contain bigint/Uint8Array (Extended JSON over the network) - Vendor sse-session, event-emitter and extended-json (no runtime deps) - Freeze child nodes so shadowed state on children fails loudly - CI on Node 22, 24 and 26 Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_017Qxbkp4tA7G5SCWjzWuxmE