"The name of the Ruby Development Tools (RDT) plug-in
and where to find the code have changed, but the basic function and
licensing terms have remained essentially unchanged. If you are new
to the idea of developing Ruby applications on Eclipse, start with
Neal Ford's article titled "Using the Ruby Development Tools
plug-in for Eclipse" to learn how to create Ruby files, how to
customize the Ruby editor, how to set up the Debugger and run Ruby
from Eclipse, as well as initiate tests from Eclipse"