How to set up TypeScript with Node.js and Express

Question

Setting up TypeScript with Node.js and Express gives you the benefits of strong typing and better tooling while building your backend server. Here's a step-by-step guide to get you started quickly.

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How to Set Up TypeScript with Node.js and Express

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1. Initialize Your Project

Open your terminal and create a new directory for your project:

mkdir my-express-ts-app
cd my-express-ts-app
npm init -y

This creates a package.json with default settings.

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2. Install Dependencies

Runtime dependencies:

npm install express

Development dependencies:

npm install -D typescript ts-node @types/node @types/express nodemon

• typescript — TypeScript compiler
• ts-node — Runs TS files directly
• @types/node — Node.js type definitions
• @types/express — Express type definitions
• nodemon — Automatically restarts server on code changes

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3. Initialize TypeScript Configuration

Run:

npx tsc --init

This creates a tsconfig.json file.

Recommended changes to tsconfig.json:

Make sure these options are set:

{
  "compilerOptions": {
    "target": "ES2020",
    "module": "commonjs",
    "outDir": "./dist",
    "rootDir": "./src",
    "strict": true,
    "esModuleInterop": true,
    "skipLibCheck": true,
    "forceConsistentCasingInFileNames": true
  }
}

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4. Create Project Structure

mkdir src
touch src/index.ts

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5. Create Express Server in TypeScript (src/index.ts)

import express, { Request, Response } from 'express';

const app = express();
const PORT = process.env.PORT || 3000;

app.get('/', (req: Request, res: Response) => {
  res.send('Hello from Express + TypeScript!');
});

app.listen(PORT, () => {
  console.log(`Server is running at http://localhost:${PORT}`);
});

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6. Add Scripts to package.json

Modify package.json to add:

"scripts": {
  "start": "node dist/index.js",
  "build": "tsc",
  "dev": "nodemon --watch 'src/**/*.ts' --exec 'ts-node' src/index.ts"
}

• npm run dev → Run server in development mode with auto reload
• npm run build → Compile TypeScript to JavaScript
• npm start → Run compiled JavaScript from dist/

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7. Run Your Server

Start development server:

npm run dev

You should see:

Server is running at http://localhost:3000

Visit http://localhost:3000 in your browser and see the message.

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Done!

You now have a basic Node.js + Express server fully set up with TypeScript.

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