Stripe billing for Next.js that handles webhook retries

Billing is where SaaS apps quietly break. Stripe retries webhooks, sends duplicates and delivers events out of order. Handle that wrong and users get Pro without paying, or paying customers stay on the free plan. Getting it right takes days of reading docs and edge cases before your first real feature.

1. Install. Unzip, run npm install, add your free Stripe test key.
2. Set up Stripe. Run npm run stripe:setup to create test products and prices, then stripe listen.
3. Gate features. Pay with the 4242 test card and protect pages server side with await requirePlan("pro").

• Full Next.js App Router plus TypeScript source code (ZIP)
• Stripe Checkout for subscriptions and one time payments (Starter, Pro, Lifetime)
• Customer Portal for cancels, card updates and plan switches
• Webhook handler with signature checks, idempotency, safe retries and out of order protection
• Plan state synced to your database with Prisma (SQLite demo, Postgres by config)
• A test suite with signed webhook payloads
• README with setup guide, architecture diagram and common pitfalls
• AGENTS.md, CLAUDE.md and Cursor rules for AI coding tools
• Unlimited projects for you or your clients, lifetime v1.x updates

• Built for Next.js App Router and Stripe. Not for other frameworks or payment providers.
• The demo login is a simple cookie login. You swap in your own auth.
• It ships in test mode and refuses live keys until you explicitly allow them. Review and test before you go live.
• It is a starting codebase, not a hosted service. You run and maintain it.

• Does it work with my auth? Yes. It needs only a user id and email. Swap in NextAuth, Clerk, Supabase or your own.
• Postgres? Change the Prisma provider and set a postgres:// DATABASE_URL.
• Do I need Stripe experience? No. Follow the setup guide. No Stripe account yet? Try checkout offline with stripe-mock.
• Can I resell it? You can use it in unlimited projects, but not resell the kit itself.
• Refunds? 14 days, no questions asked.

$49, one time.