Understand the event loop. Avoid blocking it. Master Node.js.

This book demystifies the core of Node.js — the event loop — and teaches you how to use it efficiently and safely in real-world systems.

You'll learn how Node.js schedules work, handles concurrency, and delivers performance from a single thread. More importantly, you'll discover how to avoid event loop blocking, the silent killer of performance in production.

Inside the book:

• How Node.js handles concurrency with a single thread


• The real differences between setTimeout, setImmediate, and process.nextTick


• How each event loop phase works and what code runs when


• Why non-blocking doesn't always mean fast


• How to design resilient, efficient backend architectures


• Proven techniques for avoiding event loop blocking under real workloads

Who this book is for:

• Intermediate JavaScript developers leveling up to backend Node.js


• Backend engineers who want to understand performance bottlenecks


• Educators or mentors teaching how the Node.js runtime really works


• Anyone who wants to master async behavior and concurrency in Node.js