I have a couple of gem files which I install via gem install xx.gem. Can I tell Bundler to use them? Or do I have to specify the source path?
gem install xx.gem
I would unpack your gem in the application vendor folder
gem unpack your.gem --target /path_to_app/vendor/gems/
Then add the path on the Gemfile to link unpacked gem.
gem 'your', '2.0.1', :path => 'vendor/gems/your'