---
name: react-start
description: >-
React bindings for TanStack Start: createStart, StartClient,
StartServer, React-specific imports, re-exports from
@tanstack/react-router, full project setup with React, useServerFn
hook.
type: framework
library: tanstack-start
library_version: '1.166.2'
framework: react
requires:
- start-core
sources:
- TanStack/router:packages/react-start/src
- TanStack/router:docs/start/framework/react/build-from-scratch.md
---
# React Start (`@tanstack/react-start`)
This skill builds on start-core. Read [start-core](../../../start-client-core/skills/start-core/SKILL.md) first for foundational concepts.
This skill covers the React-specific bindings, setup, and patterns for TanStack Start.
> **CRITICAL**: All code is ISOMORPHIC by default. Loaders run on BOTH server and client. Use `createServerFn` for server-only logic.
> **CRITICAL**: Do not confuse `@tanstack/react-start` with Next.js or Remix. They are completely different frameworks with different APIs.
> **CRITICAL**: Types are FULLY INFERRED. Never cast, never annotate inferred values.
## Package API Surface
`@tanstack/react-start` re-exports everything from `@tanstack/start-client-core` plus:
- `useServerFn` — React hook for calling server functions from components
All core APIs (`createServerFn`, `createMiddleware`, `createStart`, `createIsomorphicFn`, `createServerOnlyFn`, `createClientOnlyFn`) are available from `@tanstack/react-start`.
Server utilities (`getRequest`, `getRequestHeader`, `setResponseHeader`, `setResponseHeaders`, `setResponseStatus`) are imported from `@tanstack/react-start/server`.
## Full Project Setup
### 1. Install Dependencies
```bash
npm i @tanstack/react-start @tanstack/react-router react react-dom
npm i -D vite @vitejs/plugin-react typescript @types/react @types/react-dom
```
### 2. package.json
```json
{
"type": "module",
"scripts": {
"dev": "vite dev",
"build": "vite build",
"start": "node .output/server/index.mjs"
}
}
```
### 3. tsconfig.json
```json
{
"compilerOptions": {
"jsx": "react-jsx",
"moduleResolution": "Bundler",
"module": "ESNext",
"target": "ES2022",
"skipLibCheck": true,
"strictNullChecks": true
}
}
```
### 4. vite.config.ts
```ts
import { defineConfig } from 'vite'
import { tanstackStart } from '@tanstack/react-start/plugin/vite'
import viteReact from '@vitejs/plugin-react'
export default defineConfig({
plugins: [
tanstackStart(), // MUST come before react()
viteReact(),
],
})
```
### 5. Router Factory (src/router.tsx)
```tsx
import { createRouter } from '@tanstack/react-router'
import { routeTree } from './routeTree.gen'
export function getRouter() {
const router = createRouter({
routeTree,
scrollRestoration: true,
})
return router
}
```
### 6. Root Route (src/routes/\_\_root.tsx)
```tsx
import type { ReactNode } from 'react'
import {
Outlet,
createRootRoute,
HeadContent,
Scripts,
} from '@tanstack/react-router'
export const Route = createRootRoute({
head: () => ({
meta: [
{ charSet: 'utf-8' },
{ name: 'viewport', content: 'width=device-width, initial-scale=1' },
{ title: 'My TanStack Start App' },
],
}),
component: RootComponent,
})
function RootComponent() {
return (
)
}
function RootDocument({ children }: Readonly<{ children: ReactNode }>) {
return (
{children}
)
}
```
### 7. Index Route (src/routes/index.tsx)
```tsx
import { createFileRoute } from '@tanstack/react-router'
import { createServerFn } from '@tanstack/react-start'
const getGreeting = createServerFn({ method: 'GET' }).handler(async () => {
return 'Hello from TanStack Start!'
})
export const Route = createFileRoute('/')({
loader: () => getGreeting(),
component: HomePage,
})
function HomePage() {
const greeting = Route.useLoaderData()
return {greeting}
}
```
## useServerFn Hook
Use `useServerFn` to call server functions from React components with proper integration:
```tsx
import { createServerFn, useServerFn } from '@tanstack/react-start'
const updatePost = createServerFn({ method: 'POST' })
.inputValidator((data: { id: string; title: string }) => data)
.handler(async ({ data }) => {
await db.posts.update(data.id, { title: data.title })
return { success: true }
})
function EditPostForm({ postId }: { postId: string }) {
const updatePostFn = useServerFn(updatePost)
const [title, setTitle] = useState('')
return (
)
}
```
## Global Start Configuration (src/start.ts)
```tsx
import { createStart, createMiddleware } from '@tanstack/react-start'
const requestLogger = createMiddleware().server(async ({ next, request }) => {
console.log(`${request.method} ${request.url}`)
return next()
})
export const startInstance = createStart(() => ({
requestMiddleware: [requestLogger],
}))
```
## React-Specific Components
All routing components from `@tanstack/react-router` work in Start:
- `` — not needed in Start (handled automatically)
- `` — renders matched child route
- `` — type-safe navigation
- `` — declarative redirect
- `` — renders head tags (must be in ``)
- `` — renders body scripts (must be in ``)
- `` — renders deferred data with Suspense
- `` — renders children only after hydration
- `` — error boundary
## Hooks Reference
All hooks from `@tanstack/react-router` work in Start:
- `useRouter()` — router instance
- `useRouterState()` — subscribe to router state
- `useNavigate()` — programmatic navigation
- `useSearch({ from })` — validated search params
- `useParams({ from })` — path params
- `useLoaderData({ from })` — loader data
- `useMatch({ from })` — full route match
- `useRouteContext({ from })` — route context
- `Route.useLoaderData()` — typed loader data (preferred in route files)
- `Route.useSearch()` — typed search params (preferred in route files)
## Common Mistakes
### 1. CRITICAL: Importing from wrong package
```tsx
// WRONG — this is the SPA router, NOT Start
import { createServerFn } from '@tanstack/react-router'
// CORRECT — server functions come from react-start
import { createServerFn } from '@tanstack/react-start'
// CORRECT — routing APIs come from react-router (re-exported by Start too)
import { createFileRoute, Link } from '@tanstack/react-router'
```
### 2. HIGH: Using React hooks in beforeLoad or loader
```tsx
// WRONG — beforeLoad/loader are NOT React components
beforeLoad: () => {
const auth = useAuth() // React hook, cannot be used here
}
// CORRECT — pass state via router context
const rootRoute = createRootRouteWithContext<{ auth: AuthState }>()({})
```
### 3. HIGH: Missing Scripts component
Without `` in the root route's ``, client JavaScript doesn't load and the app won't hydrate.
## Cross-References
- [start-core](../../../start-client-core/skills/start-core/SKILL.md) — core Start concepts
- [router-core](../../../router-core/skills/router-core/SKILL.md) — routing fundamentals
- [react-router](../../../react-router/skills/react-router/SKILL.md) — React Router hooks and components