environment-agnostic.js

(function(root, factory) {

  // Set up Module appropriately for the environment. Start with AMD.

  if (typeof define === 'function' && define.amd) {
    define(['underscore', 'exports'], function(_, exports) {
     
      // Export global even in AMD case in case this script is loaded with others that may still expect a global "Module".
      root.Module = factory(root, exports, $);
    });

  // Next for Node.js or CommonJS.
  } else if (typeof exports !== 'undefined') {
    var _ = require('underscore');
    factory(root, exports, _);

  //Finally, as a browser global.
 
  } else {
    root.Module = factory(root, {}, root._ );
  }

}(this, function(root, Module, _, ) {

  // your library here.


  return Module;
}));

Set up a JS project to be environment agnostic. Shamelessly stolen from the beginning of Backbone

This example has Underscore as an example dependency. Use the pattern demonstrated to add any dependencies to your library. "Module" should be replaced with the name of your library's main object.