Next.js 14 with Server Components and Server Actions has transformed how we build SaaS applications. Here's our recommended architecture for production-ready SaaS products.
Folder Structure
Use the App Router with proper separation of concerns:
- (marketing) for public pages
- (dashboard) for authenticated pages
- API routes for backend logic
Key Technologies
- Framework: Next.js 14 App Router
- Database: PostgreSQL with Prisma ORM
- Auth: NextAuth.js or Clerk
- Payments: Stripe with webhook handling
- Styling: Tailwind CSS with design tokens
Server Components vs Client Components
The biggest mental shift in Next.js 14 is understanding when to use Server Components vs Client Components. Default to Server Components — they reduce bundle size and allow direct database access.
Use Client Components only when you need:
- Event handlers (onClick, onChange)
- State and lifecycle effects (useState, useEffect)
- Browser-only APIs
- Third-party libraries that use React context
Database Layer
Prisma is our go-to ORM. Define your schema declaratively, get type-safe queries, and use migrations for schema changes. For multi-tenant SaaS, implement Row Level Security (RLS) at the database level.
Authentication & Authorization
Use middleware for route protection. Implement role-based access control (RBAC) with a permissions table. Store sessions in your database for better control over active sessions.
Start with this architecture and scale as your product grows. The beauty of Next.js is that it scales from a simple landing page to a full enterprise SaaS platform.