Ruby 2.2.0-rc1 now available on Heroku
Change effective on 22 December 2014
This fully replaces Ruby 2.2.0-preview2. If you were using that release, you’ll automatically be upgraded to Ruby 2.2.0-rc1.
Note: This version of Ruby is not suitable for production applications. However, it can be used to test that your application is ready for December release of Ruby 2.2.0 and to provide feedback to the Ruby core team.