Once authenticated, an owner of the NFT can select their coffee type on their phone which then signals the Raspberry Pi to make whatever coffee type was selected by jumping the contacts that used to be pressed by the machine's buttons (which have been removed).

It's a cool gimmick, fun to show off to visitors, gives us a nice record of who is making coffee (since each NFT's owner is unique and trackable), limits users to those with the NFT without us having to build usernames/passwords, and is also how I make my coffee each afternoon.