Patir 0.2 has been released!
This is the first public release of patir giving you a command library for abstracting the execution of "commands" be it Ruby code or external programs and a way to define and load configuration files expressed in Ruby.

Take a look at the rdoc for the library.
And since you're going to want to play with it...just do a

gem install patir

You can also get the gem directly from Rubyforge