In the first week Martine spoke about the importance of Reactive Programming, I suggest you to watch the videos of the course ( Principles of Reactive Programming ). Code for video: Recap: Functions and Pattern Matching In this video there is an implementation of a Json parser with case classes, and a show methods, one possible implementation in clojure is: Here I used a simple Map with Json inside, the show method is pretty_json , instead of match I used multi function. Code for video: Functional Random Generators In this video Martin introduce the idea of functional generators to use for tests made with ScalaCheck, we will use clojurecheck that is a property base testing framework like ScalaCheck. The code of generators is: I jumped the two recap video on language because I think that who came on this blog is a clojure developer, but if you want I can make a little tutorial on clojure.