A fast browser based CSS Sprite Generator
You should be able to develop locally without any build tools. Just navigate to the site directory in a browser to test.
NOTE: some browsers do not deal well with reading files from a file:// domain (if you just opened it directly from the filesystem). It is best to develop through a web server to avoid this problem.
If you would like to create a build package, you will need rake and jekyll installed on your system. Then you can run
rake buildfrom the root directory, and it will create an output directory called site-build with the minified script references, etc.
Instant Sprite is open source under MIT License. See LICENSE.