Cli container already contains ruby, bundler.
Example:
source "https://rubygems.org"
gem 'sass', '~>3.4.0'
gem 'compass'
gem 'bootstrap-sass', '~>3.2.0'
Every developer runs bundle install to pull necessary gem dependencies
This command should be run in the folder with Gemfile:
fin exec bundle install
Two folders (.bundle, .bundler) and a file (Gemfile.lock) will be created.
Please add these directories (.bundle/.bundler) to your .gitignore file.
Run in the theme folder:
fin exec bundle exec compass compile
This is important not run compass compile directly, but run it via bundle exec so that proper gem versions were used (defined in the Gemfile).
You can run watcher to keep your CSS files up to date as changes are made:
fin exec bundle exec compass watch --poll