This book is for Clojure developers who are currently building or planning to build asynchronous and concurrent applications, and are interested in how they can apply the principles and tools of Reactive Programming to their daily jobs.
Knowledge of Clojure and Leiningen—a popular Clojure build tool—is required.
The book also features several ClojureScript examples, and as such, familiarity with ClojureScript—and web development, in general—will be helpful.
Notwithstanding, the chapters have been carefully written in such a way that as long as you possess knowledge of Clojure, following these examples should only require a little extra effort.
As this book progresses, it lays out the building blocks required by later chapters, and as such, my recommendation is that you start with Chapter 1, What is Reactive Programming?, and work your way through subsequent chapters in order.