After installing Bundler 1.1 you will get the following warning when running tests:

WARNING: Cucumber-rails required outside of env.rb. The rest of loading is being defered until env.rb is called.\
To avoid this warning, move 'gem cucumber-rails' under only group :test in your Gemfile

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The warning is misleading because it has nothing to do with moving cucumber-rails into a :test group. Instead you need to change your Gemfile to say:

gem 'cucumber-rails', :require => false