Building Mirah from the source. Prerequisite To build Mirah, we need following packages: git java, javac ant XXX: installation instructions for each OSes here. Download JRuby Mirah is written in JRuby so we need the latest JRuby distribution to build the Mirah compiler. $wget http://jruby.org.s3.amazonaws.com/downloads/1.5.2/jruby-bin-1.5.2.tar.gz $tar xvzf jruby-bin-1.5.2.tar.gz $mv jruby-1.5.2 j