Professional JavaScript (Node.js): Advanced Techniques

This book is not just another introduction to JavaScript. It is intended for developers who already write confidently in Node.js but feel they have hit a "ceiling." You will learn how to build high-load, fault-tolerant, and secure server-side applications using best practices and patterns.

The book is structured around four key areas: architecture, performance, security, and testing. Each chapter contains not only theory but also ready-to-use code examples.

What you will learn:

• How to design complex systems using Event Sourcing, CQRS, and microservice architecture in Node.js.
• A deep understanding of the Event Loop, Worker Threads, and clustering for maximum performance.
• Techniques for memory optimization, profiling, and combating leaks.
• Advanced authentication methods (JWT, OAuth 2.0, Session Management) and protection against attacks (XSS, CSRF, SQL Injection, NoSQL Injection).
• Integration, load, and unit testing using Mocha, Chai, Sinon, and Supertest.
• Working with Streams, buffers, and binary data.
• Deployment and monitoring of production applications: Docker, Kubernetes, PM2, logging, and metrics.

Who this book is for:

• Backend developers with at least 1 year of experience working with Node.js.
• Fullstack developers looking to deepen their server-side knowledge.
• Tech leads and architects who want to implement best practices in their projects.

The book is written in a lively style, with an emphasis on practical value. You will not find a retelling of documentation here — only proven techniques that the authors have applied in commercial projects with loads exceeding 100,000 requests per second.

After reading, you will be able not only to write code that works but also to create systems that are easy to scale, maintain, and secure. This is the next step in your career as a JavaScript developer.