I am using a gem which is in vendor/gems/some-api-0.1.0, copied over from another project, and added to Gemfile: gem 'some-api', :path => '~/development/myproj/vendor/gems/some-api-0.1.0' but if I do the following, it will fail with the message: $ bundle install Fetching source index for http://rubygems.org/ Could not find gem 'some-api (>= 0)' in source at ~/development/myproj/vendor/gems/some-ap