TanStack Router

Type-safe, file-based routing for React with route-level data loading, search params validation, code splitting, and TanStack Query integration.

Package: @tanstack/react-router | Plugin: @tanstack/router-plugin

Quick Reference

Pattern	Usage
createFileRoute('/path')	Define file-based route
createRootRouteWithContext<T>()	Root route with typed context
createLazyFileRoute('/path')	Code-split route component
zodValidator(schema)	Search params validation
Route.useLoaderData()	Access loader data in component
Route.useParams()	Type-safe route params
Route.useSearch()	Type-safe search params
useNavigate()	Programmatic navigation
useBlocker()	Block navigation (dirty forms)
notFound()	Throw 404 from loader
getRouteApi('/path')	Type-safe hooks in split files
stripSearchParams(defaults)	Clean default values from URLs
retainSearchParams(['key'])	Preserve params across navs
useAwaited({ promise })	Suspend until deferred promise resolves
useCanGoBack()	Check if router can go back safely

Data Loading

Method	Returns	Throws	Use Case
ensureQueryData	Data	Yes	Route loaders (recommended)
prefetchQuery	void	No	Background prefetching
fetchQuery	Data	Yes	Immediate data need
defer() (optional)	Promise	No	Stream non-critical data (promises auto-handled)

Preloading

Strategy	Behavior	Use Case
'intent'	Preload on hover/focus	Default for most links
'render'	Preload when Link mounts	Critical next pages
'viewport'	Preload when Link in view	Below-fold content
false	No preloading	Heavy, rarely-visited pages

File Organization

File	Purpose
__root.tsx	Root route with <Outlet />
index.tsx	Index route for /
posts/$postId.tsx	Dynamic param route
_authenticated.tsx	Pathless layout (auth guard)
dashboard.lazy.tsx	Code-split component

Common Mistakes

Mistake	Fix
Missing router type registration	Add declare module with Register interface
useParams() without from	Always pass from: '/route/path' for exact types
useNavigate() for regular links	Use <Link> for <a> tags, a11y, preloading
prefetchQuery in loaders	Use ensureQueryData (returns data, throws errors)
Fetching in useEffect	Use route loaders (prevents waterfalls)
Sequential fetches in loader	Use Promise.all for parallel requests
Missing leading slash	Always '/about' not 'about'
tanstackRouter() after react()	Plugin MUST come before react() in Vite config
strict: false params unparsed	Use strict mode or manually parse after navigation
Pathless route notFoundComponent	Define notFoundComponent on child routes instead
Aborted loader undefined error	Guard errorComponent with if (!error) return null
No loaderDeps declared	Declare deps so loader only re-runs when they change

Delegation

• TanStack Query patterns — data fetching, caching, mutations: use tanstack-query skill
• TanStack Start — server functions, SSR, server-side auth: use tanstack-start skill
• TanStack Table — table rendering with router search params: use tanstack-table skill
• Router + Query integration — loader data flow, preloading: see Loader Data Flow Patterns

If the tanstack-devtools skill is available, delegate router state debugging and route tree inspection to it.

References

• Setup — installation, Vite config, file structure, app setup, router default options
• Type Safety — register router, from param, strict: false, type utilities, getRouteApi
• Data Loading — route loaders, Query integration, parallel loading, streaming, deferred data, abort signal, loaderDeps
• Search Params — validation, strip/retain middleware, fine-grained subscriptions, debounce, custom serializers
• Navigation — Link, active styling, relative navigation, hash, route masks, blocker, scroll restoration
• Auth and Context — beforeLoad, context inheritance, pathless layouts, dependency injection, error handling
• Code Splitting — lazy routes, auto splitting, preloading strategies, programmatic preloading
• Virtual File Routes — rootRoute, route, index, layout, physical builders, mixing file-based and code-based routing
• Known Issues — 20 documented issues with fixes, anti-patterns
• Loader+Query Patterns — ensureQueryData in loaders, parallel loading, critical vs non-critical data, search-param-dependent loaders