steve-piece/subdomain-isolated-turborepo — reverse-engineered prompt

Build me a production ready B2B SaaS starter that lets companies sign up, get their own workspace on a custom subdomain, invite team members, and manage their organization from a secure dashboard.

I want a public marketing site on one domain and the actual customer app on a separate protected domain, with clean tenant URLs like company.myapp.com. Users should be able to create an account, verify email, set up an organization, upload branding, manage members, and have permissions based on roles like owner, admin, member, and read only. Make sure each company’s data is isolated so tenants can’t see each other.

Use Next.js, TypeScript, Supabase for auth and database, Resend for transactional emails, Vercel for deployment, and include optional Stripe billing with plans, subscriptions, limits, and upgrade prompts. Add sensible shared UI components, error tracking, tests, and setup docs so I can launch quickly and then build my actual product features on top. Look up current docs online if you need to.