TanStack Start (React) — RC-Ready Playbook

Full-stack React on TanStack Router with per-route SSR/CSR, file-based routing, server functions, and first-class Cloudflare Workers support.

Use this skill when

Building a greenfield React app that needs route-level SSR/CSR/SSG switches.
Migrating from Next.js/React Router while keeping file-based routing + API routes.
Shipping to edge runtimes (Workers) with typed server functions and bindings.
You want predictable routing with type-safe params/search + built-in preloading.

What’s inside

References: quickstart/layout, rendering modes, server functions, Cloudflare hosting, execution/auth, plus new routing/data/navigation/devtools guides.
Script:
```
scripts/bootstrap-cloudflare-start.sh <app>
```
scaffolds Start + Workers + binding types.
Troubleshooting: hydration, API routing, bindings, navigation/preloading failures.

Quick Start (React)

bash

npm create @tanstack/start@latest my-app
cd my-app
npm run dev

Manual installs (all bundle targets are supported): add

@tanstack/react-router

@tanstack/react-start

with your bundler plugin (

vite

webpack

, or

esbuild

) per the official install guides.

Core layout reminder

```
app/routes/**
```
file-based routes → router tree, automatic code-splitting + data preloading.

app/entry.client.tsx

hydrates

<StartClient />

;

app/entry.server.tsx

wraps

createServerEntry

app/config.ts

app/start.ts

sets

defaultSsr

spaMode

, middleware, and context.

Routing + Data Best Practices

Type-safe params & search:
```
createFileRoute()
```
infers path params; add
```
validateSearch
```
(zod) to parse and coerce search params.
Route matching order is deterministic (index → static → dynamic → splat); rely on this when adding catch-alls.
Loaders run once per location change; return plain data, throw
```
redirect()
```
/
```
notFound()
```
for control flow.
Data mutations: colocate
```
action
```
/server functions; keep loaders read-only and invalidate via
```
router.invalidate()
```
after mutation.
TanStack Query bridge: create a
```
QueryClient
```
in router context and
```
ensureQueryData
```
inside loaders to dedupe fetches.
Deferred/external data: stream partial data or read from external loaders; prefer suspense-friendly responses.
Head management: set
```
head
```
per route for
```
<title>
```
/meta; derive from loader data to keep SEO consistent.
Not-found/auth: throw
```
notFound()
```
or
```
redirect()
```
in loaders/middleware; use error boundaries for UX.

Example route (typed search + data-only SSR):

// app/routes/posts.$postId.tsx
import { createFileRoute, redirect } from '@tanstack/react-router'
import { z } from 'zod'

export const Route = createFileRoute('/posts/$postId')({
  validateSearch: z.object({ preview: z.boolean().optional() }),
  ssr: 'data-only',
  loader: async ({ params, search, context }) => {
    const post = await context.queryClient.ensureQueryData(['post', params.postId], () =>
      fetch(`/api/posts/${params.postId}?preview=${!!search.preview}`).then(r => r.json())
    )
    if (!post.published && !search.preview) throw redirect({ to: '/drafts' })
    return { post }
  },
})

Navigation, Preloading, and UX

Link prefetch defaults:
```
<Link preload="intent">
```
(hover/focus) preloads route data/code; use
```
preload="render"
```
for above-the-fold routes.
Programmatic preloading:
```
router.preloadRoute({ to, search })
```
to warm caches before navigation (e.g., on visibility).
Route masking: keep canonical URLs while showing user-friendly masks (e.g.,
```
/products?slug=abc
```
masked as
```
/p/abc
```
).
Navigation blocking: protect unsaved forms with
```
router.navigate({ to, replace, from })
```
blockers or
```
useBlocker
```
.
Scroll restoration: enable
```
scrollRestoration
```
to restore positions on back/forward; customize per route when using long lists.
Search param serialization: customize parse/stringify to keep numbers/dates stable and avoid stringified booleans.

Rendering & Performance

Per-route SSR: set
```
ssr: true | false | 'data-only'
```
on routes;
```
defaultSsr
```
config sets the baseline.
Code-splitting: file-based routes auto-split; add
```
lazy
```
/
```
load
```
for manual chunks on code-based routes.
Preloading strategy: pair
```
preload="intent"
```
links with
```
defaultPreloadStaleTime
```
to avoid over-fetching.
Render optimizations: keep loaders pure, memoize heavy components, and use
```
pendingComponent
```
for CSR routes to avoid layout shift.

Devtools, Linting, and LLM Support

Add
```
<RouterDevtools />
```
during development to inspect matches, loader states, and preloading.
Enable the ESLint plugin
```
@tanstack/eslint-plugin-router
```
with the recommended config to enforce inference-sensitive property order (e.g.,
```
beforeLoad
```
before
```
loader
```
).
LLM-aware routing: the Router exposes structured route metadata to LLM agents; keep descriptions concise in
```
Route
```
meta for better AI navigation.

Deployment Notes (Cloudflare-friendly)

Keep
```
cloudflare({ viteEnvironment: { name: 'ssr' } })
```
first in Vite plugins so bindings reach server entry.
Regenerate bindings after changes:
```
npm run cf-typegen
```
.
For static-heavy sites, enable prerender to ship HTML to Workers Assets/Pages; exclude param routes or add explicit
```
pages
```
.

Ship Checklist

Routes load without hydration warnings (prefer
```
ssr: 'data-only'
```
for non-deterministic UI).
Search params validated with
```
validateSearch
```
and custom serializer where needed.
Link preloading configured for high-traffic routes; blockers added for unsaved forms.

ESLint plugin enabled (

create-route-property-order

rule) and

npm run check

passes.

Devtools verified locally;
```
router.matches
```
state looks correct.
Cloudflare bindings typed (
```
cf-typegen
```
) and streaming tested via
```
curl -N
```
.

tanstack-start

NPX Install

Tags

SKILL.md Content