jrburke/backbone — comment on commit 57c2029117649452c6cf4d3337e03f5d52bb8331
File: backbone.js line 1199
By jrburke:

In the other envs, AMD and CommonJS, zepto and ender can stand in for the 'jquery' dependency. This is one of the strengths of the module formats -- by making sure zepto or ender lives at the location where 'jquery' maps to on disk, they can be used in its place.