How to Build a REST API with Next.js 14 App Router
Next.js 14 App Router makes building production-grade REST APIs simpler than ever. This step-by-step guide covers route handlers, middleware, authentication, and deployment best practices.
Back to Blog
Route Handlers Replace API Routes
Next.js 14 App Router introduces Route Handlers — files named route.ts inside the app/ directory. Unlike the older pages/api/ system, Route Handlers run as Edge or Node.js functions and support named HTTP method exports.
Structuring Your API
Organise routes as app/api/[resource]/route.ts and app/api/[resource]/[id]/route.ts. Keep business logic out of route files — delegate to service modules and repository layers that can be unit-tested independently. Use Zod for request body validation at the boundary.
Authentication with NextAuth v5
NextAuth v5 integrates natively with the App Router through middleware.ts. Protect API routes by calling auth() from next-auth at the top of your route handler — it reads the session from an httpOnly cookie and returns the authenticated user or null.
Connecting to a Database
Prisma with PlanetScale or AWS RDS is the most production-proven stack for Next.js backends. Instantiate the Prisma client as a singleton to avoid connection pool exhaustion in serverless environments.
Deploying and Monitoring
Deploy to Vercel for zero-configuration serverless hosting, or to AWS Lambda via the open-next adapter for more control. Add structured logging with Pino or Winston and connect to Datadog or CloudWatch.
Your feedback helps us grow and helps others discover our services.
Related Articles
Let's Build Your Next Project
From hosting to full-stack development — webzworld has the expertise to scale your business.