SaaS Starter Spec

A code-less repo. Specs, tests, and modules only. An agent (Claude Code) reads this folder, interviews you, and generates a tailor-made SaaS with Next.js 16.

Inspired by whenwords — same philosophy: code is the output, not the input.

How to use

1. Copy the contents of this folder into an empty directory.

2. Open Claude Code in that directory.

3. Paste this:

   Read AGENT.md and run the interview. When done, generate the project according to SPEC.md + the active modules in modules/. Then run the tests in tests/ until they all pass.

4. Pick a mode: Preset (30 sec) / Quick (1 min) / Custom (3 min).

5. The agent scaffolds, installs, runs tests, and iterates.

Available presets

• ai-saas — AI product with billing and waitlist
• waitlist — Landing + lead capture
• b2b-classic — Auth + teams + billing + contact
• solopreneur — Auth + billing + waitlist
• api-service — Paid API with key dashboard

Always-on modules (opt-out): SEO, legal pages, rate-limit, error-tracking.

Files

• SPEC.md — core of the SaaS (always generated)
• AGENT.md — interview prompt (the agent runs it)
• INSTALL.md — end-user instructions
• modules/ — specs per optional feature (auth, db, billing, email, …)
• tests/ — module tests in YAML (input/output + commands)
• CHANGELOG.md — releases
• CONTRIBUTING.md — how to add modules
• LICENSE — MIT

Generated stack

• Next.js 16 (App Router, React 19)
• TypeScript strict
• Tailwind CSS v4
• Biome (lint + format)
• pnpm
• Deploy: Vercel

Active modules are pulled on demand: Clerk or Supabase Auth, Stripe, Drizzle/Prisma, Resend, MailerLite, Sentry, PostHog, Upstash Redis, Fumadocs/Nextra, UploadThing, Vercel Cron, Claude SDK with usage tracking, etc.

License

MIT.