Useful Compass Extensions That are Worth a Try — SitePointCompass is a great Sass framework. Not only because it provides a hundred useful mixins and functions and a sprite builder, but also because it allows authors to build their own extensions, thus use other authors’ ones. A Compass extension is some kind of bundle packed as a gem, that can be installed, imported then used in your Sass stylesheets. Installing a Compass extension is a 3-step process:
Compass/SASS Mixins for Simple Retina Images on Websites » Joe Lambert
https://developers.google.com/web/tools/setup/workspace/setup-devtools
