Concurrency in TypeScript

The book "Concurrency in TypeScript" is a practical guide to building fast, responsive, and scalable applications in TypeScript. In the modern world, users expect instant interface reactions, and servers must handle thousands of requests simultaneously. This book will help you master all aspects of concurrent programming: from basic promises to advanced patterns using Web Workers and SharedArrayBuffer.

Who is this book for?

• Frontend developers who want to create smooth interfaces without blocking the UI.
• Backend developers on Node.js striving to make the most efficient use of server resources.
• Fullstack engineers who want to understand the intricacies of the event loop, microtasks, and macrotasks.
• Anyone already familiar with TypeScript who wants to take their application performance to the next level.

What will you learn?

• How the event loop works and why asynchrony does not always mean parallelism.
• Promises, async/await, and generators — when and which tool to choose.
• Error handling in concurrent code: from try/catch to the "fail-fast" pattern.
• Working with Web Workers and Worker Threads for true multithreading.
• Concurrency patterns: Producer-Consumer, Pipeline, Promise Pool, Throttling, and Debouncing.
• Data safety during concurrent access: mutexes, semaphores, and atomic operations.
• Integration with RxJS and reactive streams for complex scenarios.
• Profiling and debugging concurrent code using Chrome DevTools and Node.js Inspector.

Book structure

The book consists of 12 chapters, each containing theory, code examples, and practical tasks. You will start with the basics of asynchrony in JavaScript/TypeScript, then delve into multithreading, patterns, and finish with a full-fledged project — a concurrent web scraper on Node.js. All examples are written in TypeScript using strict typing, making the code reliable and self-documenting.

After reading, you will be able to design systems that efficiently use all CPU cores, do not block the main thread, and correctly handle thousands of simultaneous operations. The book is suitable both for learning from scratch and for deepening the knowledge of experienced developers.

Join the community of professionals writing fast and reliable code in TypeScript!