Here is my current macruby UI testing setup: Rakefile: + Has an isolate setup to pull down all my testing gems. + task build - runs xcodebuild to build a debug app + task link - runs a build and then hard links source files to build files ~/.emacs.el: + sets 'backup-by-copying-when-linked to t - allowing work on hardlinked files to go unimpeded. .autotest: + Sets ENV['RUBY'] to macruby. + Sets ENV['MACRUBY_TESTING'] to 1. + Sets ENV['GEM_HOME'] and ENV['GEM_PATH'] with expanded paths to pick up isolated gems during test runs. + initialize hook sets the test framework to minitest and runs the link rake task. + Overrides Autotest#make_test_cmd to execute the binary directly. lib/app_controller.rb: + sets $TESTING = ENV['MACRUBY_TESTING'] + applicationDidFinishLaunching requires minitest/macruby if $TESTING rb_main.rb: + needed to be tweaked to skip loading test files. So, when I fire up autotest it will build the application and then hardlink all the original source files into the build. This allows autotest to scan the lib and test dirs but invoking the application will pick up all my changes without having to rebuild. This greatly speeds up development. When autotest runs the application directly, it does so with MACRUBY_TESTING set in the environment. The application sees this and sets $TESTING to true and once the app is done launching, it loads minitest/macruby. That in turn loads up all the test files in the build dir and then runs the tests. Once the tests are run, it exits with the appropriate exit code depending on test results.