old_contents: (function(module) {
      "use strict";
  
      var twitchtv = {},
          embed = '<iframe frameborder="0" scrolling="no" src="http://twitch.tv/$1/chat?popout=" height="500" width="350"></iframe>';
  
  
      twitchtv.parse = function(postContent, callback) {
          postContent = postContent.replace(/<a href="(?:http?:\/\/)?(?:twitch\.tv)\/?(.+)">.+<\/a>/g, embed);
          callback(null, postContent);
      };
  
      module.exports = twitchtv;
  }(module));
  
new_contents: (function(module) {
      "use strict";
  
      var twitchtv = {},
          embed = '<iframe frameborder="0" scrolling="no" src="http://twitch.tv/$1/chat?popout=" height="500" width="350"></iframe>';
  
  
      twitchtv.parse = function(postContent, callback) {
          postContent = postContent.replace(/<a href="(?:www\.?)?(?:twitch\.tv)\/?(.+)">.+<\/a>/g, embed);
          callback(null, postContent);
      };
  
      module.exports = twitchtv;
  }(module));
  
subject: Replace Fail