Chapter 1. Building a Better Reactive App

This book is meant to be geared towards the more experienced Scala and Akka developers looking to build reactive applications on top of the Akka platform.

This book is written for an engineer who has already leveraged Akka in the 2.3.x series and below to build reactive applications. You have a firm understanding of the actor model and how the Akka framework leverages actors to build highly scalable, concurrent, asynchronous, event-driven, and fault-tolerant applications. You've seen the new changes rolled out in Akka 2.4.2 and are curious about how some of these new features such as Akka Streams and Akka HTTP can be leveraged within your reactive applications.

This book will serve as a guide for an engineer who wants to take a functional but flawed reactive application and, through a series of refactors, make improvements to it. It will help you understand what some of the common pitfalls are when building Akka applications. Throughout the various chapters in the book, you will learn how to use Akka and some of the newer features to address the following shortcomings:

• Building a more domain-centric model using domain-driven design
• Using event sourcing and Akka Persistence for high throughput persistence
• Understanding reactive streams and how Akka makes use of them in Akka Streams and Akka HTTP
• Decomposing a monolith into a set of fully decoupled and independent services