Suck is a project mainly written in SHELL and RUBY, it's free.
gem to show issues with gem/minigem load ordering
cfp:~/src/git/suck > ls lib/ rails.rb suck.rb
cfp:~/src/git/suck > cat lib/rails.rb abort('suck')
cfp:~/src/git/suck > sudo minigem prepare suck Installed minigems at /opt/local/lib/ruby/site_ruby/1.8/minigems.rb
cfp:~/src/git/suck > ruby -r minigems -e"require 'suck'; require 'rails';" suck