Take your React knowledge to the next level with advanced concepts, strategies, techniques, patterns and in-depth investigations.This book is a must You've gone through the React docs, implemented a few simple apps, and now are "How can I progress to the next level?"You've been working with React for a few years and you're confident that you know it inside and out. This book might have a surprise or two for you.You want to become the go-to person for everything React performance and be the source of in-depth and "how things actually work and " knowledge in your team.But why?React docs are very good to start with React. Millions of books, courses, and blogs are out there aimed at beginners. But what to do after you've started successfully? Where to go if you want to understand how things work on a deeper level? What to read if you've been writing React for a while and beginner or even intermediate-level courses are not enough? There are not many resources available for this. This is the gap this book aims to fill.What the book aims to provide is the knowledge that allows you to progress from and "can implement a basic todo app and " to and "React guru in my team and ". It begins right away with investigating and fixing a performance bug. It digs deep into what re-renders are and how they affect performance. Walks you through how the reconciliation algorithm works, how to deal with closures in React, various composition patterns that can replace memoization, how memoization works, how to implement debouncing correctly, and much more.The book is very structured. Each chapter is an independent story, investigation, or deep dive focusing on a single topic. However, they are not completely each chapter builds on the knowledge introduced in the previous chapters. Also, each chapter tries to introduce only the knowledge required to understand the discussed concept, no more. To make the reading easier and more focused.If your knowledge already extends beyond the simple and "todo and " app, it's very likely that you'll know a lot of the concepts already. For this case, every chapter has a bullet-point list of things you can expect to learn from it at the beginning, and a and "Key takeaways and " section, with a very short bullet-point summary of the things introduced. Just skimming through these first will give you a good idea of what's inside.You can read the book from cover to cover, and I tried to make sure you'll have fun doing that. Or just focus on things that matter to you the most and skim through the and "Key takeaways and " sections of the rest of the chapters.I'm new to React. Is this book a good fit for me?The book's target audience is people who are already familiar with React. Ideally, they have implemented an app or two and now want to progress to the next level. If you're a complete beginner, the book may not be the best fit. It starts with investigating a small performance problem right away and assumes that the reader can implement at least a simple and "todo and " app by themselves.You'll definitely need the book after a few months into your React journey though.