Most Java developers have overlooked the Java 9 REPL. This new feature will enable you to make scripts and do live coding with Java using the new 'jshell'. In this talk I'll guide you through the process of building jshell and we'll do live coding to learn how it works and behaves. After this quickie you'll not only be able to build but also use jshell, OpenJDK needs more users to find bugs, make tests and improve this new addition to your JDK9/bin directory.