You will need Java installed. The app will download any additional dependencies.
From the shell
./sbt compile
The project depends on Scala and its build tool,
sbt. If the sbt script fails to install Scala and SBT, you can manually install them.
On OS X, assuming you have homebrew installed, the easiest way to install these is via:
brew install scala sbt
Alternatively, you can download native OS packages from the links above.