Building a Scalable RESTful API with Node.js and Express

Architecting Node.js for Production

While Express is straightforward to set up, building an API that scales to thousands of concurrent requests requires strict modular architecture and defensive programming.

1. Controller-Service-Repository Pattern

Decouple HTTP routing from business logic and database access. Routes handle parameters, services orchestrate domain rules, and repositories interact with the database.

2. Centralized Error Handling Middleware

app.use((err, req, res, next) => {
  const status = err.statusCode || 500;
  res.status(status).json({
    success: false,
    message: err.message || 'Internal Server Error',
    ...(process.env.NODE_ENV === 'development' && { stack: err.stack }),
  });
});

3. JWT Authentication & Rate Limiting

Secure endpoints with JSON Web Tokens and defend against brute-force attacks using Redis-backed rate limiting middleware.