I just started using the editor and curious what should I use to reformat the code, like a beautifier script etc.
Nothing for Ruby yet.
But, this is a great opportunity to contribute if you feel like, you can get inspiration from those packages and create a beautifier for ruby or add support for Ruby on one of the existing packages.
apm init --package ~/.atom/packages/code-beautifier --convert https://github.com/mocoso/code-beautifier.tmbundle.git
There are no errors thrown but an empty package is created with simply a Readme file and a default package.json file.