Here is a Gemfile of default Rails application.
source 'https://rubygems.org'
gem 'rails', '4.1.0'
gem 'sqlite3'
gem 'sass-rails', '~> 4.0.3'
gem 'uglifier', '>= 1.3.0'
gem 'coffee-rails', '~> 4.0.0'
gem 'jquery-rails'
gem 'turbolinks'
gem 'jbuilder', '~> 2.0'
gem 'sdoc', '~> 0.4.0',          group: :doc
gem 'tzinfo-data', platforms: [:mingw, :mswin]
Whei I run bundle install everything is intalled fine.
Now do
gem install cramp
It is being installed also without any troubles.
And finally include
gem 'cramp'
into Gemfile. From now on we have following results:
bundle install
DL is deprecated, please use Fiddle
Fetching gem metadata from https://rubygems.org/..........
Fetching additional metadata from https://rubygems.org/..
Resolving dependencies...
Bundler could not find compatible versions for gem "activesupport":
  In Gemfile:
    cramp (>= 0) x86-mingw32 depends on
      activesupport (= 3.0.pre) x86-mingw32
    rails (= 4.1.0) x86-mingw32 depends on
      railties (= 4.1.0) x86-mingw32 depends on
        activesupport (4.1.0)
bundle update
DL is deprecated, please use Fiddle
Fetching gem metadata from https://rubygems.org/..........
Fetching additional metadata from https://rubygems.org/..
Resolving dependencies...
Bundler could not find compatible versions for gem "thor":
  In Gemfile:
    cramp (>= 0) x86-mingw32 depends on
      thor (~> 0.14.6) x86-mingw32
    rails (= 4.1.0) x86-mingw32 depends on
      railties (= 4.1.0) x86-mingw32 depends on
        thor (0.19.1)
Bundler could not find compatible versions for gem "activesupport":
  In Gemfile:
    cramp (>= 0) x86-mingw32 depends on
      activesupport (= 3.0.pre) x86-mingw32
    rails (= 4.1.0) x86-mingw32 depends on
      activesupport (4.1.0)
I did not specify a Cramp version so there must be used the same version as I installed with gem install cramp. But why gem install worked without any problems and bundle install has found some unresolved dependencies?
I am trying to do all this on Windows 7 + Ruby 2.0.0p451 + Rails 4.1.0 and on Ubuntu 12.04 LTS with the same Ruby and Rails versions.
What I tried: I ran bundle install and bundle update on default Gemfile, then added gem 'cramp', ran bundle install and bundle update again. Results you can see few lines above.
 
                        
It seems Cramp is inactive from last 4 months and it doesn't support Rails 4
Here are some more alternatives for Cramp Gem
Alternatives for Cramp Gem