How does rollback work when the server rejects an optimistic mutation?
When the server responds with an error, the UI reverts the local state to its pre-mutation value, typically showing an error toast. The mutation is then queued with an idempotency key and retried when connectivity is restored or after a backoff delay. Users see a clear error message and the option to retry.
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?
- What is an idempotency key and why does it prevent double-charging or duplicate inserts?
- How do you handle ordering when mutations are queued offline and replayed later?
- When is optimistic UI the wrong call and what should you use instead?
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