Have you used Express.js in real-world projects under production conditions?

Yes, Express.js is widely used in real projects for creating server applications on Node.js due to its simplicity and flexibility. It allows for quick setup of routing, request handling, and integration with various middleware, making it a convenient choice for developing REST APIs and web applications.

Example of a simple server on Express.js:

const express = require('express');
const app = express();

app.get('/', (req, res) => {
  res.send('Hello World!');
});

app.listen(3000, () => {
  console.log('Server is running on port 3000');
});