Authentication
Sign-up and login pages with email verification. Social login and magic links depend on the providers you configure in Convex.
Authentication docsNEXTBASE FOR TANSTACK START
TanStack Start SaaS starter kit
For teams that want TanStack Start for routing and Convex for the backend. Your users sign up, create a workspace and manage projects on day one, and an admin area is included.
The TanStack Start kit is the TanStack + Convex starter. It ships with a Next.js + Convex repo, so you can choose the framework after you buy.
- App layer
- TanStack Start
- Backend
- Convex with reactive queries
- Login
- Convex Auth
- Hosting
- Vercel + Convex
ARCHITECTURE
How the TanStack Start kit is built
The repo is a monorepo with the website and the Convex backend in separate apps.
- Website:
apps/web, with TanStack Start routing and Convex queries and mutations. - Backend: schema and functions live in
apps/database/convex/. Convex runs the backend and Vercel hosts the website. - Authentication: Convex Auth, configured in the selected Convex deployment.
- Agent connections: the user and admin MCP servers live on the Convex HTTP endpoint, with code in
apps/database/convex/mcp/.
WHAT IS INCLUDED
Accounts, workspaces and an admin area
Workspaces and projects
Projects belong to a workspace, and the app checks membership before it returns any workspace data. Workspace owners manage their workspace.
Workspace docsAdmin area and agent access
Application administrators get a separate admin area. Users can connect an agent to one workspace; in this kit it can also create a project once the user approves write access.
Tools and permissionsStripe billing is included in every paid plan and connects to your own Stripe account. Email delivery uses Resend through the Convex deployment's environment variables.
SUPPORTED BACKENDS
Every TanStack kit, by backend
Only the Convex kit runs on TanStack Start. Check the app layer before you pick a backend.
| Kit | App layer | Database | Login provider | Demo hosting | Links |
|---|---|---|---|---|---|
| TanStack + Supabase | React Router + Express, with TanStack Query | Supabase Postgres | Supabase Auth | Vercel | Demo of TanStack + SupabaseDocs for TanStack + Supabase |
| TanStack + Convex | TanStack Start | Convex | Convex Auth | Vercel + Convex | Demo of TanStack + ConvexDocs for TanStack + Convex |
| TanStack + Neon | React Router + Express, with TanStack Query | Neon Postgres | Better Auth | Vercel | Demo of TanStack + NeonDocs for TanStack + Neon |
| TanStack + Cloudflare D1 | React Router on Workers, with TanStack Query | Cloudflare D1 | Better Auth | Cloudflare Workers | Demo of TanStack + Cloudflare D1Docs for TanStack + Cloudflare D1 |
SETUP
From clone to a running app
Use Node.js 24 and the pnpm version pinned in the repository.
- Clone the private repositoryYou get access to the GitHub repository after checkout.
- Start a local Convex backendThe local backend keeps development state in
.convex/, and a guard checks that you are on a local deployment. - Create an account and a workspaceSign up, verify your email and add a project so you have data to work with.
- DeployDeploy the website on Vercel, publish the backend on Convex, and set
MCP_APP_URLto your website origin.
pnpm install
pnpm db:local:init
pnpm db:local:select
pnpm auth:setup
pnpm dev:localFull steps are in the TanStack + Convex setup guide.
AFTER PURCHASE
What you change first
- Your Convex deployment, app origin and auth callback URLs.
- A verified sending domain for Resend, so verification emails reach users.
- The social login providers you want to offer.
- Your Stripe products and keys, if you charge for plans.
- Your own tables and functions in
apps/database/convex/, and any new MCP tools, kept behind the same permission checks.
DECISION GUIDE
TanStack Start or Next.js?
Both Convex repos come with the same purchase, so you can try each one.
Choose TanStack Start
If your team already uses TanStack Router and Query, wants type-safe routes from one router, and is happy with Convex as the backend.
TanStack + Convex demoChoose Next.js
If you want the App Router and React Server Components, or a backend other than Convex. There are Next.js kits for Supabase, Convex, Neon and Cloudflare D1.
Next.js + Convex demoCompare every stack on the Nextbase home page or in Choose your starter.
PRICING
Convex kit pricing
Pay once. The Convex purchase includes the TanStack Start repo and the Next.js repo.
Solo
Best for indie makers
$299Pay once. Use forever
Buy SoloStartup
Best for growing teams
$599Pay once. Use forever
Buy StartupBusiness
Best for organizations
$849Pay once. Use forever
Buy BusinessCompare every feature by plan in the full pricing table.
FAQ
Questions about the TanStack Start kit
Is every Nextbase TanStack kit built on TanStack Start?
No. The TanStack + Convex kit uses TanStack Start. The TanStack kits for Supabase, Neon and Cloudflare D1 use React Router with TanStack Query. The table on this page lists the app layer for each one.
What do I get when I buy the Convex kit?
Access to the private GitHub repositories for the Convex stack: the TanStack Start repo and the Next.js App Router repo. You also get the documentation, lifetime updates and the support included in your plan.
Can I use the TanStack Start kit with Supabase?
Not today. The TanStack + Supabase kit uses React Router, Express and TanStack Query with Supabase Auth. If you want Supabase with the Next.js App Router, see the Next.js + Supabase starter kit.
Where does the TanStack Start kit run?
The documented setup deploys the website on Vercel and publishes the backend separately on Convex. The Cloudflare Workers guide in the docs covers the two D1 kits.
Is billing set up for me?
Stripe integration is part of every paid plan. It uses your own Stripe account, so you add your keys and test checkout and subscription changes on your deployment before launch.
Can I use the kit for client or commercial projects?
You can build your own products with Nextbase and charge your customers. You cannot resell Nextbase as a starter kit. Pick the plan with enough seats for the developers on your team.
How do updates and support work?
Your purchase includes lifetime updates; pull new changes from the repository when you are ready. Email admin@arni-creative.com for support, and join the Discord server you are invited to after purchase.
Do you offer refunds?
No. Nextbase purchases are not refundable. Try the live demo and read the docs first, and email admin@arni-creative.com with any questions before you buy.