TypeScript

xpress-generator has first-class TypeScript support. When you answer "Yes" to the TypeScript prompt, every generated file uses .ts extensions and proper TypeScript syntax.

---

Enabling TypeScript

During project creation, answer Yes when prompted:

? Use TypeScript? › Yes

That's it. The CLI generates:

• All source files as .ts
• tsconfig.json pre-configured
• ts-node for development
• ts-jest for testing
• All necessary @types/* packages installed

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TypeScript configuration

The generated tsconfig.json:

{
  "compilerOptions": {
    "target": "ES2020",
    "module": "commonjs",
    "lib": ["ES2020"],
    "outDir": "./dist",
    "rootDir": "./src",
    "strict": true,
    "esModuleInterop": true,
    "allowSyntheticDefaultImports": true,
    "resolveJsonModule": true,
    "skipLibCheck": true
  },
  "include": ["src/**/*", "tests/**/*"],
  "exclude": ["node_modules", "dist"]
}

Key options explained

Option	Why
"module": "commonjs"	Compatible with Node.js require()
"strict": true	Enables all strict checks for safer code
"esModuleInterop": true	Allows import express from 'express' syntax
"outDir": "./dist"	Compiled output goes to dist/

---

npm scripts

TypeScript projects get these scripts in package.json:

{
  "scripts": {
    "dev":   "ts-node src/server.ts",
    "start": "node dist/server.js",
    "build": "tsc",
    "test":  "jest --coverage"
  }
}

Command	Description
npm run dev	Run with ts-node (no compile step, fast for development)
npm run build	Compile TypeScript to dist/
npm start	Run the compiled JavaScript from dist/
npm test	Run tests with ts-jest

---

TypeScript file examples

Controller

import { Request, Response, NextFunction } from 'express';
import catchAsync from '../utils/catchAsync';
import httpResponse from '../utils/httpResponse';

export const index = catchAsync(
  async (req: Request, res: Response): Promise<void> => {
    httpResponse.success(res, { message: 'API running' });
  }
);

Custom request type

The generated auth.ts middleware extends Express's Request interface so req.user is typed everywhere:

declare global {
  namespace Express {
    interface Request {
      user?: { id: string; role: string };
    }
  }
}

Service layer

import Model from '../models/myAppModel';

export async function getAll() {
  return Model.find();
}

export async function getById(id: string) {
  return Model.findById(id);
}

---

Generated @types packages

For TypeScript projects, the following dev dependencies are installed automatically:

@types/node
@types/express
@types/jsonwebtoken
@types/bcryptjs
@types/cors
@types/morgan
@types/cookie-parser
@types/supertest

---

Building for production

npm run build

Output is placed in dist/. To run in production:

npm start
# equivalent to: node dist/server.js

tip

Always run npm run build before deploying. The compiled JavaScript in dist/ is what runs in production — ts-node is only for development.

---

Generating code in a TypeScript project

The generate:model and generate:middleware commands read .xpress.json to detect the project language and automatically generate .ts files:

npx xpress-generator generate:model Product
# generates src/models/productModel.ts (not .js)