Dynamic router in Durandal 2.0

The router configuratin is in the shell.js file. I need to make this router dynamically managable. To do so, I have used ajax.

The change is in the active method in shell.js file.

activate: function () {
   var routes = [];
 
   $.ajax({
       url: "/Route/Get",
       async: false,
       dataType  : 'json'
       }).done(function (response) {
       routes = response;
   });
 
   router.map(routes).buildNavigationModel();
   return router.activate();
}

The server code is as below.

public JsonResult Get()
  {
     List route = new List()
     {
        new Route(){ route = "" ,title = "Welcome", moduleId = "viewmodels/welcome", nav= true },
        new Route(){ route = "flickr" , moduleId = "viewmodels/flickr" , nav= true }
     };

     return Json(route , JsonRequestBehavior.AllowGet);
}