This gem adds a single generator to Rails 3, mootools:install. Running the generator will remove any Prototype JS files you may happen to have, fetch MooTools Core and the MooTools-ujs driver for Rails.
The gem will also hook into the Rails configuration process, removing Prototype and adding MooTools to the javascript files included by the javascript_include_tag(:defaults) call. While the plugin downloads minified and un-minified version of MooTools, only the minified versions are included in :default.
In your Gemfile, add this line:
gem "mootools-rails"
Then, run bundle install. To invoke the generator, run:
rails generate mootools:install --version to install specific version of MooTools (default is 1.2.5)
You're done! Don't forget to output csrf_meta_tag somewhere inside your <head> tag in your layout!