tanstack-query

TanStack Query v5 manages server state through useQuery for fetching data and useMutation for updates. Wrap your app with QueryClientProvider, then call useQuery({ queryKey, queryFn }) to fetch and automatically cache responses. The library handles synchronization, background refetching, and stale-data management without manual Redux or Context boilerplate.

staleTime controls how long cached data is considered fresh; queries return immediately without refetching during this window. gcTime (formerly cacheTime) determines how long unused cached data persists in memory before garbage collection. Set staleTime to reduce network requests and gcTime higher to preserve data across component unmounts.

TanStack Query v5 migration replaces cacheTime with gcTime, adopts object syntax for useQuery and useMutation, and introduces queryOptions factories for reusable configurations. Use migration codemods to automate renaming, then refactor hooks to leverage the new patterns. Dependencies remain the same; the upgrade is primarily API and naming changes.

Yes. TanStack Query v5 supports optimistic updates through useMutation's onMutate callback to update cache before the server responds. Infinite queries use useInfiniteQuery with a getNextPageParam function to paginate through results, automatically managing page state and combining responses into a single queryKey.

Configure retry count and delay in QueryClient or per-mutation. useMutation automatically retries failed requests based on these settings. Capture errors in the onError callback to display user feedback. Use throwOnError to control whether mutations throw or silently fail, and combine with error boundaries for granular error handling.

Use queryOptions factory to define queryKey, queryFn, staleTime, and gcTime in one place, then pass the result to useQuery. This centralizes configuration, improves type safety, and makes queries reusable across components. DevTools integration automatically logs all query activity for debugging cache and fetch behavior.