// the find
vercel/platforms
A full-stack Next.js app with multi-tenancy.
Vercel's reference implementation for subdomain-based multi-tenancy in Next.js — each tenant gets a `tenant.yourdomain.com` route resolved through the new proxy layer (Next 16's replacement for middleware). It's aimed at people building a SaaS-style app who need a working starting point for subdomain routing, not a library or framework.
The proxy-based subdomain detection actually handles the three environments that matter (local `.localhost` dev, Vercel preview URLs, and production custom domains) instead of only working in one. Tenant storage is a simple Redis key pattern (`subdomain:{name}`), which is easy to read and swap out if you don't want Upstash. It's kept current with the ecosystem — Next.js 16, React 19, Tailwind 4 — so you're not learning patterns that got replaced two major versions ago.
There's no tenant isolation beyond routing — no per-tenant auth, permissions, or data scoping, so anyone using this as a real SaaS starting point has to build the actual multi-tenancy security model themselves. Redis-as-database is fine for a demo but is a real limitation the moment you need relational data, migrations, or anything beyond key lookups. No tests at all, so the subdomain-detection logic in `proxy.ts` — the trickiest part of the whole repo — is unverified beyond manual testing. Single flat tenant model with no custom-domain-per-tenant support, which most real multi-tenant products need eventually.