TanStack Query for Next.js

TanStack Query v5 provides powerful server state management with Next.js 16 integration.

Agent Workflow (MANDATORY)

Before ANY implementation, use TeamCreate to spawn 3 agents:

1. fuse-ai-pilot:explore-codebase - Analyze existing data fetching patterns
2. fuse-ai-pilot:research-expert - Verify latest TanStack Query v5 docs
3. mcp__context7__query-docs - Check TanStack Query + Next.js patterns

After implementation, run fuse-ai-pilot:sniper for validation.

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Overview

When to Use

• Client-side data fetching with caching and revalidation
• Server-side prefetching with hydration to client
• Optimistic updates for mutations
• Infinite scrolling and pagination
• Real-time data synchronization

Why TanStack Query

Feature	Benefit
Server prefetching	Data ready on first render, no loading flash
Automatic caching	Deduplication, stale-while-revalidate
Mutations	Optimistic updates, rollback on error
DevTools	Visual cache inspection
TypeScript-first	Full type inference

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Critical Rules

1. One QueryClient per request - Create in Server Component, share via context
2. Prefetch in Server Components - Use prefetchQuery for SSR data
3. HydrationBoundary required - Wrap client tree to transfer server cache
4. Query keys must be serializable - Arrays of strings/numbers only
5. staleTime on prefetched queries - Prevent immediate refetch on mount
6. Never use queryClient in Client Components directly - Use hooks

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Installation

bun add @tanstack/react-query @tanstack/react-query-devtools

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Best Practices

1. Prefetch on server - Avoid loading states for critical data
2. Set staleTime - Prevent unnecessary refetches after hydration
3. Collocate query keys - Define keys near their usage
4. Invalidate on mutation - Use invalidateQueries after writes
5. Error boundaries - Use throwOnError for critical queries
6. DevTools in dev only - Wrap in process.env.NODE_ENV check

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Reference Guide

Need	Reference
useQuery, useMutation	query-patterns.md
Server prefetching	hydration.md
QueryClient setup	hydration.md
Cache invalidation	query-patterns.md