old_contents: var http = require("http");
  var ShareDB = require("sharedb");
  var connect = require("connect");
  var serveStatic = require('serve-static');
  var ShareDBMingoMemory = require('sharedb-mingo-memory');
  var WebSocketJSONStream = require('websocket-json-stream');
  var WebSocket = require('ws');
  var util = require('util');
  var Duplex = require('stream').Duplex;
  
  // Start ShareDB
  var share = ShareDB({db: new ShareDBMingoMemory()});
  
  // Create a WebSocket server
  var app = connect();
  app.use(serveStatic('.'));
  var server = http.createServer(app);
  var wss = new WebSocket.Server({server: server});
  server.listen(8080);
  console.log("Listening on http://localhost:8080");
  
  // Connect any incoming WebSocket connection with ShareDB
  wss.on('connection', function(ws, req) {
    var stream = new WebSocketJSONStream(ws);
    share.listen(stream);
  });
  
  // Create initial documents
  var connection = share.connect();
  connection.createFetchQuery('players', {}, {}, function(err, results) {
    if (err) { throw err; }
  
    if (results.length === 0) {
      var names = ["Ada Lovelace", "Grace Hopper", "Marie Curie",
                   "Carl Friedrich Gauss", "Nikola Tesla", "Claude Shannon"];
  
      names.forEach(function(name, index) {
        var doc = connection.get('players', ''+index);
        var data = {name: name, score: Math.floor(Math.random() * 10) * 5};
        doc.create(data);
      });
    }
  });
  
new_contents: var http = require("http");
  var ShareDB = require("sharedb");
  var connect = require("connect");
  var serveStatic = require('serve-static');
  var ShareDBMingoMemory = require('sharedb-mingo-memory');
  var WebSocketJSONStream = require('websocket-json-stream');
  var WebSocket = require('ws');
  var util = require('util');
  
  // Start ShareDB
  var share = ShareDB({db: new ShareDBMingoMemory()});
  
  // Create a WebSocket server
  var app = connect();
  app.use(serveStatic('.'));
  var server = http.createServer(app);
  var wss = new WebSocket.Server({server: server});
  server.listen(8080);
  console.log("Listening on http://localhost:8080");
  
  // Connect any incoming WebSocket connection with ShareDB
  wss.on('connection', function(ws, req) {
    var stream = new WebSocketJSONStream(ws);
    share.listen(stream);
  });
  
  // Create initial documents
  var connection = share.connect();
  connection.createFetchQuery('players', {}, {}, function(err, results) {
    if (err) { throw err; }
  
    if (results.length === 0) {
      var names = ["Ada Lovelace", "Grace Hopper", "Marie Curie",
                   "Carl Friedrich Gauss", "Nikola Tesla", "Claude Shannon"];
  
      names.forEach(function(name, index) {
        var doc = connection.get('players', ''+index);
        var data = {name: name, score: Math.floor(Math.random() * 10) * 5};
        doc.create(data);
      });
    }
  });
  
subject: Remove unused Duplex variable in example