How do you handle ordering when mutations are queued offline and replayed later?
Offline mutations are stored in a queue in the order they were attempted. When connectivity is restored, the queue replays sequentially, not in parallel. Each mutation waits for its server ACK before the next begins. This ensures dependent operations (e.g., create a post, then add a comment) complete in the correct order.
Answered in
Optimistic UI: The Illusion of InstantApply mutations locally and reconcile in the background, collapsing perceived latency from 150 ms to instant. Rollback, idempotency keys, offline queues.
Read the full analysisOther questions this article answers
- What is optimistic UI execution and why is perceived latency different from actual latency?
- How does rollback work when the server rejects an optimistic mutation?
- What is an idempotency key and why does it prevent double-charging or duplicate inserts?
- When is optimistic UI the wrong call and what should you use instead?
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