Google Closure's codebase, which powers Gmail, etc. is well over 33MB, and ExtJS' size includes image assets, etc. So you can see that this is a poor metric. e

Google Closure's codebase, which powers Gmail, etc. is well over 33MB, and ExtJS' size includes image assets, etc. So you can see that this is a poor metric. ext-base.js and ext-all.js, minified, are fairly light. Further, there's no ExtJS builder that I am aware of, so there are no optional "modules." I'm not sure what you're talking about. While the components are technically decoupled, using a GridPanel without Ext.data's offerings, for instance, would be pretty clunky.