This is great news for the Ext-JS community. Here is why you should take advantage of a content delivery network.
The Ext CDN also provides the ability to create your own custom builds using Ext’s Build It! tool, and host them on the CDN. The custom builder implements features to intelligently cache your component selections, adapter, and Ext version to create a unique custom build. These custom builds are cached across sessions and used by anyone who makes the same selections as you have – allowing for caching of custom builds across applications to fully realize the benefits of the CDN.