How to Build Your First REST API with Node.js and TypeScript in 2026
Backend development can feel intimidating when you're starting out. But building a REST API is one of the clearest, most practical skills you can develop — and with Node.js and TypeScript in 2026, the tooling makes it more approachable than ever.
This tutorial walks you through building a real API from scratch: project setup, routing, database connection, validation, authentication, and deployment basics.
What You'll Build
A simple but complete REST API for a blog platform — endpoints to create, read, update, and delete posts, with JWT-based authentication and MongoDB as the database. By the end you'll have something real that you can extend and deploy.
Project Setup
Start by initializing a new project with Bun or Node.js. Install Express, Mongoose, Zod for validation, and the TypeScript toolchain. Configure your tsconfig.json with strict mode enabled from the start. Structure your folders with clear separation between routes, controllers, models, and middleware — this pattern scales well as the project grows.
Defining Your Models
Use Mongoose to define your data models with TypeScript interfaces alongside your schemas. Keeping the interface and schema in sync is the most important discipline in a Node/Mongo project. Zod schemas for request body validation sit alongside your Mongoose models and act as your first line of defense against bad input.
Routing and Controllers
Keep your route files thin — just the HTTP method, path, middleware chain, and a reference to a controller function. All business logic lives in controllers. All database queries live in a service layer below that. This separation makes testing, debugging, and refactoring dramatically easier.
Authentication with JWT
Implement a simple auth flow: register stores a hashed password with bcrypt, login returns a signed JWT, and a middleware function verifies that token on protected routes. Store only the user ID in the token payload. Keep token expiry short and implement refresh token rotation for anything user-facing.
Validation and Error Handling
Every route that accepts a request body should validate it with a Zod schema before it touches your controller. Create a global error handler middleware that catches thrown errors and returns consistent JSON responses. Never let raw error messages reach the client in production.
Deployment Basics
Railway, Render, and Fly.io are the easiest paths to a deployed Node.js API in 2026. Use environment variables for all secrets — never hardcode database URIs or JWT secrets. Set up a basic health check endpoint so your hosting platform can verify the service is running.