How do you handle race conditions in Redux?

A race condition happens when multiple async requests are in flight and they resolve out of order — e.g., a user types quickly in a search box, an older request for "re" resolves after the newer request for "react", overwriting the correct results with stale ones.

1. createAsyncThunk + request tracking: store the latest requestId and ignore results from stale requests.

  const fetchResults = createAsyncThunk("search/fetch", async (query) => {
    const res = await fetch(`/api/search?q=${query}`);
    return res.json();
  });

  builder.addCase(fetchResults.fulfilled, (state, action) => {
    // Only apply the result if it belongs to the most recent request
    if (action.meta.requestId === state.currentRequestId) {
      state.results = action.payload;
    }
  });

2. Abort stale requests using AbortController, which createAsyncThunk supports via thunkAPI.signal — cancel the previous request when a new one starts.
3. Debounce/throttle the trigger (e.g., debounce keystrokes) so fewer overlapping requests are made in the first place.
4. Use RTK Query, which automatically de-duplicates in-flight requests, cancels/ignores stale ones, and keeps the cache consistent without manual bookkeeping.