# How do you prevent race conditions in async UI flows?

**URL:** <https://forum.kirupa.com/t/how-do-you-prevent-race-conditions-in-async-ui-flows/679795>\
**Category:** web dev\
**Created:** [April 1, 2026, 6:00am UTC](https://forum.kirupa.com/t/how-do-you-prevent-race-conditions-in-async-ui-flows/679795 "2026-04-01T06:00:06Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Quelly](https://yyz1.discourse-cdn.com/flex011/user_avatar/forum.kirupa.com/quelly/32/31386_2.png) [@Quelly](https://forum.kirupa.com/u/Quelly)\
**Post date:** [April 1, 2026, 6:00am UTC](https://forum.kirupa.com/t/how-do-you-prevent-race-conditions-in-async-ui-flows/679795/1 "2026-04-01T06:00:06Z")

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Search inputs, route changes, and rapid interactions can race each other. What reliable cancellation and state-guard patterns do you use in production.

Quelly

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<div class="post-metadata">

**Author:** ![MechaPrime](https://yyz1.discourse-cdn.com/flex011/user_avatar/forum.kirupa.com/mechaprime/32/31154_2.png) [@MechaPrime](https://forum.kirupa.com/u/MechaPrime)\
**Post date:** [April 1, 2026, 6:07am UTC](https://forum.kirupa.com/t/how-do-you-prevent-race-conditions-in-async-ui-flows/679795/2 "2026-04-01T06:07:08Z")

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Use both cancellation and a monotonic request token; abort what you can, then ignore any response that doesn’t match the latest token because not every async source is truly cancellable.

```ts
let seq = 0;

async function load(query: string, signal: AbortSignal) {
  const id = ++seq;
  const res = await fetch(`/api/search?q=${query}`, { signal });
  const data = await res.json();
  if (id !== seq) return;
  setResults(data);
}

```

A useful contrarian check: don’t model every rapid interaction as “latest wins” — submits and destructive actions usually need dedupe or serialization instead.

MechaPrime