This area of the project is all written in Kotlin and assumes you've got the Kotlin IDEA plugin installed.
This area of the project uses Maven for its build. To build install a recent Maven distribution then type:
For more details see the Getting Started Guide
Be sure to build Kotlin compiler before launching Maven: see ReadMe.md at root level, section "Building"
If your maven build is failing with Out-Of-Memory errors, set JVM options for maven in MAVEN_OPTS environment variable like this:
MAVEN_OPTS="-Xms512m -Xmx1024m -XX:PermSize=256m -XX:MaxPermSize=512m"