Write Node.js code that scales, whether it comes from you or AI, and avoid the anti-patterns that cause performance and production problems

Key Features

• Identify and fix common Node.js anti-patterns before they impact production
• Avoid performance bottlenecks by understanding Node.js internals
• Apply proven patterns to write clean, maintainable, and scalable Node.js code

Book Description

Node.js makes it easy to get started, but just as easy to get things wrong.

Whether you're writing code yourself or using AI in your development workflow, How Not to Node.js takes a practical, no-nonsense approach to uncovering the most common mistakes developers make, and shows you exactly how to avoid them.

The book is structured around real-world anti-patterns, guiding you through how to identify, understand, and fix problematic code. You’ll start by learning how patterns and anti-patterns shape application design, before diving into asynchronous pitfalls, event loop behavior, and error handling. As you progress, you’ll explore architectural concerns such as logging, environment management, and memory leaks.

By the end, you won’t just know how to write or review Node.js code, you’ll know how to avoid writing bad Node.js code, building applications that are clean, scalable, and production-ready.

What you will learn

• Recognize common JavaScript and Node.js anti-patterns and refactor them effectively
• Write clean, maintainable code by avoiding common code smells and bad practices
• Manage environment variables securely and efficiently
• Keep the event loop responsive by avoiding blocking code and offloading CPU-heavy work
• Diagnose and fix memory leaks using profiling and heap analysis tools
• Handle asynchronous operations correctly using promises and async/await

Who this book is for

This book is for Node.js developers who want to level up from writing code that works to writing code that scales.

Whether you’re an early-career developer struggling with asynchronous patterns or an experienced engineer dealing with performance and production issues, this book will help you identify what’s going wrong and how to fix it.

Table of Contents

1. Understanding the Concept of Patterns and Anti-patterns
2. Spotting and Solving Anti-patterns in JavaScript
3. Staying Away from Smelly Code
4. Dealing with the Most Common Anti-patterns in Node.js
5. Understanding Promises and Callbacks
6. Logging Done Right
7. Taming Your Environment
8. What is Synchronous and What is Asynchronous
9. Memory Leaks and Where They Come From
10. Unlock the Code Bundle and the PDF Version

About the Author

Lucas Santosis a Brazilian engineer, an eight-time Microsoft MVP, a seven-time GoogleDeveloper Expert, and a former Docker Captain living in Stockholm, Sweden. He has beenprogramming professionally since 2011 and has worked at big corporations such as Microsoftand Klarna, as well as at several startups. He is currently a staff engineer at Detectify. He is anavid content creator and has been writing about tech content on his blog at lsantos.dev for over10 years. He has presented over 150 talks in several countries. He is a former member and corecontributor of the Node.js core team and has contributed to multiple open-source projects.When he is not writing code, he is usually playing music, building guitar pedals, or 3D printingsomething he probably does not need.