google closure

http://erik.eae.net/archives/2009/11/05/22.27.29/

At the time we were considering using Dojo as our base for this new library. We were very impressed with Dojo but back then Dojo was too unstable and we had heard too many horror stories of upgrade migration head aches. We also looked at MochiKit which was more stable but it did not really solve any of our problems. (*)

http://www.moretechtips.net/2009/11/getting-closer-to-google-closure.html
http://blog.louisgray.com/2009/11/story-and-impact-of-closure-googles.html
http://blog.ericsk.org/archives/1366
Closure Library API Documentation
java -jar compiler.jar --compilation_level ADVANCED_OPTIMIZATIONS --js hello.js --js_output_file output.js