You should possess a basic knowledge of the Scala programming language, have some familiarity with elementary functional programming concepts, and have experience of writing production-level JVM software. We recommend that readers who are new to Scala and functional programming spend some time studying other resources before reading this book in order to get the best out of it. Two excellent Scala-centric resources are Programming in Scala, Artima Press and Functional Programming in Scala, Manning Publications. The former is best suited for strong object-oriented Java programmers that are looking to understand the language first and the functional programming paradigm second. The latter focuses heavily on the functional programming paradigm and less so on language-specific constructs.