code: function createUser(req, res, next){
  
          // the HTML form names are conveniently named the same as
          // the UserApp fields...
          var user = req.body;
  
          // Create the user in UserApp
          UserApp.User.save(user, function(err, user){
  
              // We can just pass through messages like "Password must be at least 5 characters." etc.
              if (err) return res.render('signup', {user: false, message: err.message});
  
              // UserApp passport needs a username parameter
              req.body.username = req.body.login;
  
              //on to authentication
              next();
          });
  
      // authenticate the user using passport
  }
docs: first we need to create the user in UserApp