Less.js should be defined as a [CommonJS/AMD](http://wiki.commonjs.org/wiki/Modules/AsynchronousDefinition) module. This can be done unobtrusively by adding the following code: ``` if (typeof define === "function" && define.amd) { define("less", [], function () { return less; } ); } ``` This standard is being embraced by many libraries, such as jQuery 1.7 (see: http://bugs.jquery.com/ticket/7102)