 <p>In getting started with reactjs I ran into the issue and as a beginner the <a href="http://requirejs.org/docs/errors.html#mismatch" rel="nofollow">docs</a> may as well been written in greek.</p> <p>The issue I ran into was that most of the beginner examples use "anonymous defines" when you should be using a "string id". </p> <p><strong>anonymous defines</strong></p> <pre><code>define(function() { return { helloWorld: function() { console.log('hello world!') } }; }) define(function() { return { helloWorld2: function() { console.log('hello world again!') } }; }) </code></pre> <p><strong>define with string id</strong></p> <pre><code>define('moduleOne',function() { return { helloWorld: function() { console.log('hello world!') } }; }) define('moduleTwo', function() { return { helloWorld2: function() { console.log('hello world again!') } }; }) </code></pre> <p>When you use <strong>define with a string id</strong> then you will avoid this error when you try to use the modules like so:</p> <pre><code>require([ "moduleOne", "moduleTwo" ], function(moduleOne, moduleTwo) { moduleOne.helloWorld(); moduleTwo.helloWorld2(); }); </code></pre>