Build HTTP APIs with routing, middleware, validation, controllers, and error handling.
Lessons
Solve beginner Express problems and explain each result.
Express Practice Problems is easiest to learn by reading the example, changing it, and observing the result.
import express from 'express';
const app = express();
app.use(express.json());
app.get('/api/lessons', (req, res) => {
res.json([{ slug: 'express-routing', title: 'Express Routing' }]);
});
app.post('/api/lessons', (req, res) => {
res.status(201).json({ created: true, title: req.body.title });
});
app.listen(process.env.PORT || 3000);Practice the Express Practice Problems example in a small scratch file, then explain what changed and why.