Ion-nav-buttons makes ion-nav-back-button disappear

Hello, I am new to ionic and I am trying to have both a back button and an additional button on the <ion-nav-bar>
For some reason when I add the <ion-nav-buttons side="secondary"> the back button disappears.

Below is the template I am trying to work on (which renders inside the main <ion-nav-view></ion-nav-view>)

Any help is very much appreciated. Thank you

<ion-view view-title="Login">
  <ion-nav-bar class="bar-stable">
    <ion-nav-back-button>
    </ion-nav-back-button>
  </ion-nav-bar>
  <ion-nav-buttons side="secondary">
        <button class="button" ng-click="doSomething()">
          primary btn
        </button>
  </ion-nav-buttons>
  <ion-content>
      .....
  </ion-content>