How to manage the back hardware button?

[nobady90]

Hi, I find great (even better than the official) your approach to creating a stack containing the Drawer.

I have a problem however with the back hardware button, I can not figure out how to handle it, currently from any page comes out of the app. here I reproduced my situation, similar to yours: https://snack.expo.io/BkB4ojRxm

Thank's a lot!