Tappybara: Niemand hat die Absicht, Bargeld zu digitalisieren! (dhcp25)

At our Saarländisches Chaos-Event Mega-Knowledgecamp, we created an Innovative Digital Platform™ to have digital payments at the bar, without involving American payment acquirers and networks. This talk will present the many NFC crimes we committed to enable this. Let's admit it, dealing with cash at a bar, particularly notes with wet hands, is a bit of a faff. In September we held the first edition of the Saarland's first chaos event, Mega-Knowledgecamp. Obviously, we needed a bar, but we didn't want to be dealing with cash at the bar; neither did we want to be using the primarily American payment networks and acquirers for payments. As a solution to this dilemma, we decided to create our own payment system for the bar. Attendees could pre-book bar credit and pay via bank transfer, or hand over cash at the help desk. Payment could then be made at the bar using the ticket barcode, or using the digital wallet feature of Google phones over NFC - just like a bank card! This talk will cover how we built this system, how the NFC protocols of Google and Apple Wallet work, the insane level of NDAs required to implement this, and how you can use this yourself. Licensed to the public under https://creativecommons.org/licenses/by/4.0/ about this event: https://talks.dhcp.cfhn.it/dhcp25/talk/KUTQB3/