We'd like to let you know that in the next week we'll be scheduling work to update the default version of Ruby in the Ruby Buildpack from 2.2.x to 2.3.x. This change only affects application that don't specify the version of Ruby in the Gemfile.
Please let us know if this is an undesired change. Also, please keep in mind that you can always force the buildpack to use a specific version of ruby by adding the following line to your `Gemfile`: