This book is a missed opportunity.
Akka is a wonderful framework that allows designing asynchronous non blocking distributed applications. The literature covering Akka and reactive programming is scarce and fragmented. The examples online are limited and often uninteresting. The "best practices" or "patterns" of Akka programming are only very briefly documented in the Akka online documentation.
This book could have filled all of those gaps by being both an introductory guide to actor programming and a reference guide for advanced patterns and concepts like actor supervision and self-healing, routing, remoting, clustering (actually not covered because not finalized at the time the book was published).
Instead, the author gets lost in his own sense of humor and horribly unpractical and contrived example (as others have noticed) that not only doesn't help understanding any pattern or best practice, but it also makes the first steps in actor programming much harder because it's too abstract and meaningless to give the reader some simple "real life" examples to work from.
Instead, the reader has to do the extra work of abstracting the concepts out of the (annoyingly "funny") text and the non-sense monolithic example (for which no complete source code is given, which makes it even harder to follow) and try to figure out how those concepts actually apply to a real system design, e.g., how to interact with a (blocking) database driver or other service, how and where to implement fault tolerance for the most critical parts of the system, how to distribute actors or actor systems across many machines for high availability, etc. None of this is covered with clarity in the book.
Moreover, the book isn't able to make a solid case for reactive programming and Akka by focusing on the unpractical code examples but also by lacking a clear and concise explanation of the advantages of non-blocking paradigms vs more traditional approaches.
I was expecting much more out of this. A much better book is Effective Akka by Jamie Allen (Effective Akka Jamie Allen which gives concise coding examples, spells out the advantages of reactive programming and its typical use cases, provides usable patterns and best practices in the form of real life code bits and simple and focused design recommendations. I was able to start designing my system after reading just a few pages of that book, while I got nowhere reading Akka Concurrency.