Building a SaaS Platform with React & Next.js: Architecture Guide
Learn how to architect a production-grade SaaS application with Next.js App Router, React Server Components, multi-tenancy, authentication, and scalable database design.
Next.js 14+ with the App Router is the strongest foundation for modern SaaS platforms. Here's how we architect production-grade SaaS applications.
Tech Stack
- **Frontend**: Next.js App Router, React Server Components, Tailwind CSS
- **Backend**: Next.js API routes + tRPC or REST
- **Database**: PostgreSQL with Prisma ORM
- **Auth**: NextAuth.js or Clerk
- **Hosting**: Vercel (frontend) + AWS (backend services)
Multi-Tenancy Architecture
Use a shared database with tenant isolation via row-level security (RLS) in PostgreSQL. Each tenant gets a workspace with isolated data, configurable branding, and role-based access.
Authentication & Authorization
Implement JWT-based auth with refresh tokens. Use middleware for route protection. Define roles: Owner, Admin, Member, Viewer—with granular permissions per feature.
Database Design Principles
- Normalize core entities, denormalize for read performance - Use UUID primary keys for distributed systems - Implement soft deletes for audit trails - Add created_at/updated_at timestamps on every table
Scaling Strategy
- Use ISR (Incremental Static Regeneration) for marketing pages - Server Components for dashboard (no client JS bundle) - Edge middleware for geo-routing - Connection pooling with PgBouncer for database scaling