When I do sudo gem install XYZ where does that code actually go? Are gems written in ruby on another language?
When I do bundle install, what does that do? I read throug
in your console use command:
gem env
There will be INSTALLATION DIRECTORY
The command
bundle install
installs the gems listed in your Gemfile. If you are installing gems using bundle, you can type
bundle show <gem name>
to see the directory that it is installed in. If I were you I'd navigate to one of those directories and view the code -- it's usually ruby code (but can sometimes involve C). (Look in the 'lib' subdir first -- that's where most of the code usually is).