Node.js underpins much of modern web development, reliably powering APIs and full-stack apps across all industries. Authors Luciano Mammino and Mario Casciaro offer a practical guide that unpacks the JavaScript runtime so you can write reliable, high-performance Node.js apps. Building on the highly rated third edition, this new edition adds fresh case studies and the latest Node.js developments: newer APIs and libraries, ESM improvements, practical security and production tips, and guidance on using Node.js with TypeScript. It also introduces a new chapter on testing that gives you a full introduction to testing philosophy and practical guidance on writing unit, integration, and end-to-end tests, giving you the confidence to write functional, stable, and reliable code. Real-world, end-to-end examples throughout the book show how to build microservices and distributed systems with Node.js, integrating production-proven technologies such as Redis, RabbitMQ, LevelDB, and ZeroMQ, the same components you’ll find in scalable deployments at companies of all sizes. End-of-chapter exercises consolidate your understanding. By the end of this Node.js book, you’ll have the design patterns, mindset, and hands-on skills every serious Node.js professional needs to confidently architect robust, efficient, and maintainable applications.