Building a Full-Stack SaaS with Next.js, Prisma & PostgreSQL

Next.js has evolved into a powerful full-stack framework. Here's how I architect SaaS applications using the App Router, Server Components, and modern tooling. ## The Stack - **Next.js** — Full-stack React framework - **Prisma** — Type-safe ORM - **PostgreSQL** — Relational database - **Tailwind CSS** — Utility-first styling - **NextAuth** — Authentication - **Stripe** — Payments ## Key Architecture Decisions ### Server Components by Default React Server Components are the default in the App Router. Use them for data fetching and keep Client Components for interactivity. This dramatically reduces the JavaScript bundle sent to the client. ### API Routes as Microservices Treat API routes as self-contained microservices. Each route handler should validate input, authenticate the user, perform the business logic, and return a structured response. ### Database-First Development Define your Prisma schema first, then build the API and UI around it. This ensures your data model drives the application architecture.