AI Saas Starter

ai-saas-starter

The free, open-source AI SaaS boilerplate and starter kit for Next.js 16.

Auth, Stripe subscriptions, an append-only credits ledger, and AI image
generation — built as an AI-native repo that Claude Code, Cursor, and
Codex can extend without breaking the money paths.

Live demo ·
Deploy guide ·
Pro version

What is this?

- This website is the demo — sign up,
  everything works.
- The code is a free GitHub repo — MIT, clone it.
- You build YOUR product on top — auth and payments are done.

A free, open-source SaaS boilerplate / starter kit for Next.js 16 ·
React 19 · TypeScript strict · Better Auth · Drizzle + PostgreSQL ·
Stripe · AI SDK 6 · Tailwind v4 + shadcn/ui · Resend · Vitest +
Playwright.

See it

Why another SaaS boilerplate?

AI assistants are good at building product features and bad at the 20% that
loses money when improvised: webhook retries, concurrent spends, refund
paths, idempotency. This repo ships that 20% finished and tested — an
append-only credit ledger whose balance is enforced equal to
SUM(amount), Stripe webhooks that verify raw-body signatures and survive
replays, a double-spend race test against real Postgres — plus the context
files (AGENTS.md, rules, skills, hooks) that keep an agent from quietly
unpicking any of it while you vibe-code the product on top.

Quickstart (60 seconds)

That boots with graceful degradation: no Stripe keys → billing page shows a
setup card; no Resend key → emails no-op with a console warning; no OAuth
keys → those buttons hide; AI_MOCK=true → image generation is free and
offline. Every variable is documented in .env.example.

Quickstart for AI agents

Paste this into your coding agent:

Works with Claude Code, Cursor, Codex, Copilot, and Gemini CLI. The repo
briefs the agent itself — AGENTS.md,…