TanStack Start on Cloudflare

Build a complete full-stack app from nothing. Claude generates every file — no template clone, no scaffold command. Each project gets exactly what it needs.

What You Get

Layer	Technology
Framework	TanStack Start v1 (SSR, file-based routing, server functions)
Frontend	React 19, Tailwind v4, shadcn/ui
Backend	Server functions (via Nitro on Cloudflare Workers)
Database	D1 + Drizzle ORM
Auth	better-auth (Google OAuth + email/password)
Deployment	Cloudflare Workers

Project File Tree

PROJECT_NAME/
├── src/
│   ├── routes/
│   │   ├── __root.tsx              # Root layout (HTML shell, theme, CSS import)
│   │   ├── index.tsx               # Landing / auth redirect
│   │   ├── login.tsx               # Login page
│   │   ├── register.tsx            # Register page
│   │   ├── _authed.tsx             # Auth guard layout route
│   │   ├── _authed/
│   │   │   ├── dashboard.tsx       # Dashboard with stat cards
│   │   │   ├── items.tsx           # Items list table
│   │   │   ├── items.$id.tsx       # Edit item
│   │   │   └── items.new.tsx       # Create item
│   │   └── api/
│   │       └── auth/
│   │           └── $.ts            # better-auth API catch-all
│   ├── components/
│   │   ├── ui/                     # shadcn/ui components (auto-installed)
│   │   ├── app-sidebar.tsx         # Navigation sidebar
│   │   ├── theme-toggle.tsx        # Light/dark/system toggle
│   │   ├── user-nav.tsx            # User dropdown menu
│   │   └── stat-card.tsx           # Dashboard stat card
│   ├── db/
│   │   ├── schema.ts               # Drizzle schema (all tables)
│   │   └── index.ts                # Drizzle client factory
│   ├── lib/
│   │   ├── auth.server.ts          # better-auth server config
│   │   ├── auth.client.ts          # better-auth React hooks
│   │   └── utils.ts                # cn() helper for shadcn/ui
│   ├── server/
│   │   └── functions.ts            # Server functions (CRUD, auth checks)
│   ├── styles/
│   │   └── app.css                 # Tailwind v4 + shadcn/ui CSS variables
│   ├── router.tsx                  # TanStack Router configuration
│   ├── client.tsx                  # Client entry (hydrateRoot)
│   ├── ssr.tsx                     # SSR entry
│   └── routeTree.gen.ts            # Auto-generated route tree (do not edit)
├── drizzle/                        # Generated migrations
├── public/                         # Static assets (favicon, etc.)
├── vite.config.ts
├── wrangler.jsonc
├── drizzle.config.ts
├── tsconfig.json
├── package.json
├── .dev.vars                       # Local env vars (NOT committed)
└── .gitignore

Dependencies

Runtime:

{
  "react": "^19.0.0",
  "react-dom": "^19.0.0",
  "@tanstack/react-router": "^1.120.0",
  "@tanstack/react-start": "^1.120.0",
  "drizzle-orm": "^0.38.0",
  "better-auth": "^1.2.0",
  "zod": "^3.24.0",
  "class-variance-authority": "^0.7.0",
  "clsx": "^2.1.0",
  "tailwind-merge": "^3.0.0",
  "lucide-react": "^0.480.0"
}

Dev:

{
  "@cloudflare/vite-plugin": "^1.0.0",
  "@tailwindcss/vite": "^4.0.0",
  "@vitejs/plugin-react": "^4.4.0",
  "tailwindcss": "^4.0.0",
  "typescript": "^5.7.0",
  "drizzle-kit": "^0.30.0",
  "wrangler": "^4.0.0",
  "tw-animate-css": "^1.2.0"
}

Scripts:

{
  "dev": "vite",
  "build": "vite build",
  "preview": "vite preview",
  "deploy": "wrangler deploy",
  "db:generate": "drizzle-kit generate",
  "db:migrate:local": "wrangler d1 migrations apply PROJECT_NAME-db --local",
  "db:migrate:remote": "wrangler d1 migrations apply PROJECT_NAME-db --remote"
}

Workflow

Step 1: Gather Project Info

Required	Optional
Project name (kebab-case)	Google OAuth credentials
One-line description	Custom domain
Cloudflare account	R2 storage needed?
Auth method: Google OAuth, email/password, or both	Admin email

Step 2: Initialise Project

Create the project directory and all config files from scratch.

vite.config.ts — Plugin order matters. Cloudflare MUST be first:

import { defineConfig } from "vite";
import { cloudflare } from "@cloudflare/vite-plugin";
import { tanstackStart } from "@tanstack/react-start/plugin/vite";
import tailwindcss from "@tailwindcss/vite";
import viteReact from "@vitejs/plugin-react";

export default defineConfig({
  plugins: [
    cloudflare({ viteEnvironment: { name: "ssr" } }),
    tailwindcss(),
    tanstackStart(),
    viteReact(),
  ],
});

wrangler.jsonc:

{
  "$schema": "node_modules/wrangler/config-schema.json",
  "name": "PROJECT_NAME",
  "compatibility_date": "2025-04-01",
  "compatibility_flags": ["nodejs_compat"],
  "main": "@tanstack/react-start/server-entry",
  "account_id": "ACCOUNT_ID",
  "d1_databases": [
    {
      "binding": "DB",
      "database_name": "PROJECT_NAME-db",
      "database_id": "DATABASE_ID",
      "migrations_dir": "drizzle"
    }
  ]
}

Key points: main MUST be "@tanstack/react-start/server-entry" (Nitro server entry). Use nodejs_compat (NOT node_compat). Add account_id to avoid interactive prompts.

tsconfig.json:

{
  "compilerOptions": {
    "target": "ES2022",
    "module": "ESNext",
    "moduleResolution": "bundler",
    "jsx": "react-jsx",
    "strict": true,
    "skipLibCheck": true,
    "esModuleInterop": true,
    "resolveJsonModule": true,
    "isolatedModules": true,
    "noEmit": true,
    "paths": { "@/*": ["./src/*"] },
    "types": ["@cloudflare/workers-types/2023-07-01"]
  },
  "include": ["src/**/*", "vite.config.ts"]
}

.dev.vars — generate BETTER_AUTH_SECRET with openssl rand -hex 32:

BETTER_AUTH_SECRET=<generated-hex-32>
BETTER_AUTH_URL=http://localhost:3000
TRUSTED_ORIGINS=http://localhost:3000
# GOOGLE_CLIENT_ID=
# GOOGLE_CLIENT_SECRET=

.gitignore — node_modules, .wrangler, dist, .output, .dev.vars, .vinxi, .DS_Store

Then install and create the D1 database:

cd PROJECT_NAME && pnpm install
npx wrangler d1 create PROJECT_NAME-db
# Copy the database_id into wrangler.jsonc d1_databases binding

Step 3: Database Schema

src/db/schema.ts — All tables. better-auth requires: users, sessions, accounts, verifications. Add application tables (e.g. items) for CRUD demo.

D1-specific rules:

• Use integer for timestamps (Unix epoch), NOT Date objects
• Use text for primary keys (nanoid/cuid2), NOT autoincrement
• Keep bound parameters under 100 per query (batch large inserts)
• Foreign keys are always ON in D1

src/db/index.ts — Drizzle client factory:

import { drizzle } from "drizzle-orm/d1";
import { env } from "cloudflare:workers";
import * as schema from "./schema";

export function getDb() {
  return drizzle(env.DB, { schema });
}

CRITICAL: Use import { env } from "cloudflare:workers" — NOT process.env. Create the Drizzle client inside each server function (per-request), not at module level.

drizzle.config.ts:

import { defineConfig } from "drizzle-kit";

export default defineConfig({
  schema: "./src/db/schema.ts",
  out: "./drizzle",
  dialect: "sqlite",
});

Generate and apply the initial migration:

pnpm db:generate
pnpm db:migrate:local

Step 4: Configure Auth

src/lib/auth.server.ts — Server-side better-auth:

import { betterAuth } from "better-auth";
import { drizzleAdapter } from "better-auth/adapters/drizzle";
import { drizzle } from "drizzle-orm/d1";
import { env } from "cloudflare:workers";
import * as schema from "../db/schema";

export function getAuth() {
  const db = drizzle(env.DB, { schema });
  return betterAuth({
    database: drizzleAdapter(db, { provider: "sqlite" }),
    secret: env.BETTER_AUTH_SECRET,
    baseURL: env.BETTER_AUTH_URL,
    trustedOrigins: env.TRUSTED_ORIGINS?.split(",") ?? [],
    emailAndPassword: { enabled: true },
    socialProviders: {
      // Add Google OAuth if credentials provided
    },
  });
}

CRITICAL: getAuth() must be called per-request (inside handler/loader), NOT at module level.

src/lib/auth.client.ts — Client-side auth hooks:

import { createAuthClient } from "better-auth/react";

export const { useSession, signIn, signOut, signUp } = createAuthClient();

src/routes/api/auth/$.ts — API catch-all for better-auth:

import { createAPIFileRoute } from "@tanstack/react-start/api";
import { getAuth } from "../../../lib/auth.server";

export const APIRoute = createAPIFileRoute("/api/auth/$")({
  GET: ({ request }) => getAuth().handler(request),
  POST: ({ request }) => getAuth().handler(request),
});

CRITICAL: Auth MUST use an API route (createAPIFileRoute), NOT a server function (createServerFn). better-auth needs direct request/response access.

Step 5: Server Functions

Core pattern — always create DB client inside the handler:

import { createServerFn } from "@tanstack/react-start";
import { getDb } from "../db";

export const getItems = createServerFn({ method: "GET" }).handler(async () => {
  const db = getDb();
  return db.select().from(items).all();
});

Input validation with Zod:

export const createItem = createServerFn({ method: "POST" })
  .inputValidator(
    z.object({
      name: z.string().min(1),
      description: z.string().optional(),
    })
  )
  .handler(async ({ data }) => {
    const db = getDb();
    const id = crypto.randomUUID();
    await db.insert(items).values({ id, ...data, createdAt: Date.now() });
    return { id };
  });

Protected server functions — check auth, throw redirect if unauthenticated:

import { redirect } from "@tanstack/react-router";
import { getAuth } from "../lib/auth.server";

async function requireSession(request?: Request) {
  const auth = getAuth();
  const session = await auth.api.getSession({
    headers: request?.headers ?? new Headers(),
  });
  if (!session) {
    throw redirect({ to: "/login" });
  }
  return session;
}

export const getSessionFn = createServerFn({ method: "GET" }).handler(
  async ({ request }) => {
    const auth = getAuth();
    return auth.api.getSession({ headers: request.headers });
  }
);

export const getItems = createServerFn({ method: "GET" }).handler(
  async ({ request }) => {
    const session = await requireSession(request);
    const db = getDb();
    return db.select().from(items).where(eq(items.userId, session.user.id)).all();
  }
);

Route loader pattern — server functions in route loader:

export const Route = createFileRoute("/_authed/items")({
  loader: () => getItems(),
  component: ItemsPage,
});

function ItemsPage() {
  const items = Route.useLoaderData();
  return <div>{items.map((item) => <div key={item.id}>{item.name}</div>)}</div>;
}

Auth guard (_authed.tsx) — use beforeLoad:

export const Route = createFileRoute("/_authed")({
  beforeLoad: async () => {
    const session = await getSessionFn();
    if (!session) {
      throw redirect({ to: "/login" });
    }
    return { session };
  },
});

Child routes access session via Route.useRouteContext().

Mutation + invalidation — after mutations, invalidate router to refetch loaders:

function CreateItemForm() {
  const router = useRouter();
  const handleSubmit = async (data: NewItem) => {
    await createItem({ data });
    router.invalidate();
    router.navigate({ to: "/items" });
  };
  return <form onSubmit={...}>...</form>;
}

Type safety — use Drizzle's InferSelectModel / InferInsertModel for server function input/output types. For auth failures, always use throw redirect() — not error responses.

Step 6: App Shell + Theme

src/routes/__root.tsx — Root layout with full HTML document, <HeadContent /> and <Scripts /> from @tanstack/react-router. Add suppressHydrationWarning on <html> for SSR + theme toggle compatibility. Import global CSS. Include inline theme init script to prevent flash.

src/styles/app.css — @import "tailwindcss" (v4 syntax), CSS variables for shadcn/ui tokens in :root and .dark, neutral/monochrome palette. Use semantic tokens only.

src/router.tsx:

import { createRouter as createTanStackRouter } from "@tanstack/react-router";
import { routeTree } from "./routeTree.gen";

export function createRouter() {
  return createTanStackRouter({ routeTree });
}

declare module "@tanstack/react-router" {
  interface Register {
    router: ReturnType<typeof createRouter>;
  }
}

src/client.tsx and src/ssr.tsx — standard TanStack Start entry point boilerplate.

Install shadcn/ui (configure to use src/components):

pnpm dlx shadcn@latest init --defaults
pnpm dlx shadcn@latest add button card input label sidebar table dropdown-menu form separator sheet

Theme toggle: three-state (light -> dark -> system -> light). Store in localStorage. Apply .dark class on <html>. Use JS-only system preference detection — NO CSS @media (prefers-color-scheme) queries.

Components in src/components/: app-sidebar.tsx (navigation), theme-toggle.tsx, user-nav.tsx (dropdown with sign-out), stat-card.tsx.

Step 7: CRUD Server Functions

Function	Method	Purpose
getItems	GET	List all items for current user
getItem	GET	Get single item by ID
createItem	POST	Create new item
updateItem	POST	Update existing item
deleteItem	POST	Delete item by ID

Each server function: (1) gets auth session, (2) creates per-request Drizzle client via getDb(), (3) performs DB operation, (4) returns typed data. Route loaders call GET functions. Mutations call POST functions then router.invalidate().

Step 8: Verify Locally

pnpm dev

• App loads at http://localhost:3000
• Register a new account (email/password)
• Login and logout work
• Dashboard loads with stat cards
• Create, list, edit, delete items
• Theme toggle cycles: light -> dark -> system
• Sidebar collapses on mobile
• No console errors

Step 9: Deploy to Production

Pre-deploy checklist:

• wrangler.jsonc has correct account_id
• D1 database created and database_id set
• main is "@tanstack/react-start/server-entry"
• nodejs_compat in compatibility_flags
• .dev.vars is in .gitignore
• No hardcoded secrets in source

Set production secrets:

openssl rand -hex 32 | npx wrangler secret put BETTER_AUTH_SECRET
echo "https://PROJECT.SUBDOMAIN.workers.dev" | npx wrangler secret put BETTER_AUTH_URL
echo "http://localhost:3000,https://PROJECT.SUBDOMAIN.workers.dev" | npx wrangler secret put TRUSTED_ORIGINS

If using Google OAuth:

echo "your-client-id" | npx wrangler secret put GOOGLE_CLIENT_ID
echo "your-client-secret" | npx wrangler secret put GOOGLE_CLIENT_SECRET

Add production redirect URI in Google Cloud Console: https://PROJECT.SUBDOMAIN.workers.dev/api/auth/callback/google

Migrate and deploy:

pnpm db:migrate:remote
pnpm build && npx wrangler deploy

After first deploy: update BETTER_AUTH_URL with actual Worker URL, then redeploy.

Post-deploy verification:

• App loads at production URL
• Auth login/register works
• CRUD operations work
• Theme persists across page loads

Custom domain (optional): Add in Cloudflare Dashboard -> Workers -> Triggers -> Custom Domains. Update BETTER_AUTH_URL and TRUSTED_ORIGINS secrets with the custom domain. Update Google OAuth redirect URI. Redeploy.

Common Issues

Symptom	Cause	Fix
env is undefined	Accessed at module level	Use import { env } from "cloudflare:workers" inside request handler only
D1 database not found	Binding mismatch	Check d1_databases binding name in wrangler.jsonc matches code
Auth redirect loop	URL mismatch	BETTER_AUTH_URL must match actual URL exactly (protocol + domain, no trailing slash)
Auth silently fails	Missing origins	Set TRUSTED_ORIGINS secret with all valid URLs (comma-separated)
Styles not loading	Missing plugin	Ensure @tailwindcss/vite plugin is in vite.config.ts
SSR hydration mismatch	Theme flash	Add suppressHydrationWarning to <html> element
Build fails on Cloudflare	Bad config	Check nodejs_compat flag and main field in wrangler.jsonc
Secrets not taking effect	No redeploy	wrangler secret put does NOT redeploy — run npx wrangler deploy after
Auth endpoints return 404	Wrong route type	Use createAPIFileRoute (API route), not createServerFn for better-auth
"redirect_uri_mismatch"	Missing URI	Add production URL to Google Cloud Console OAuth redirect URIs
Cryptic Vite errors	Plugin order	Must be: cloudflare() -> tailwindcss() -> tanstackStart() -> viteReact()
"Table not found" 500s	Missing migration	Run pnpm db:migrate:remote before deploying