Debugging

Debugging checklist

Make sure you didn’t specify id as an attribute in your model

App.User = DS.Model.extend({
  // THIS IS WRONG!
  id: DS.attr("string"),

  username: DS.attr("string")
});

the model should look like this instead

App.User = DS.Model.extend({
  username: DS.attr("string")
});

since Ember Data will handle the id automatically.