How to install a gem from GitHub URL rather than RubyGems. This is useful for plugins which you have not published on RubyGems. This is not so useful for themes because you can just use Remote Themes Plugins on GH Pages.

Based on How to install gems from git repositories doc.

Requirements

The repo must have a .gemspec file at the root.

Setup

Add it to your Gemfile:

gem 'GEMNAME', git: 'https://github.com/USERNAME/REPO_NAME'

Example:

gem 'rack', git: 'https://github.com/rack/rack

Install it.

$ bundle install

Then you can use the gem.