Next.js + Supabase + Stripe

The full SaaS stack in one combo

Next.js + Supabase covers the app. Stripe covers the money. Together, they deliver everything a subscription SaaS needs: auth, multi-tenancy, billing, prorating, dunning, refunds, customer-managed cancellations.

How the billing wiring actually works

The naive integration is "redirect to Stripe Checkout, hope for the best." The production-grade pattern:

1. Customer hits the upgrade button — server action creates a Stripe Checkout session with metadata containing the workspace ID.
2. Customer pays — Stripe redirects them back to a success page with a polling check.
3. In parallel, Stripe sends a checkout.session.completed webhook to /api/stripe/webhook.
4. The webhook handler verifies the signature, looks up the workspace ID from the metadata, and writes a row to the workspace_subscriptions table.
5. The Supabase realtime channel notifies the success page that the subscription is active. Page redirects to dashboard.

Idempotency keys on every Stripe call prevent double-billing if a webhook is retried. The subscription table is the source of truth — never trust the user's session claim of "I'm on Pro," always check the database.

What I include by default

• 3-tier pricing page (Solo / Team / Enterprise) — easy to add more.
• Free trial logic — configurable per tier, automatic conversion or downgrade.
• Customer Portal integration — users self-serve cancellations, downgrades, payment method updates.
• Dunning flow — failed-payment retry logic, customer notification emails, automatic suspension after N retries.
• Annual + monthly cycles with proration on tier changes.