The many frameworks of Cocoa Touch are the cornerstone of modern iOS apps. What happens when the building blocks start to work against you? Sam Marshall will take you through the lifecycle of a bug encountered at Tinder on the eve of the launch of iOS 12. To this day, it is one of the most puzzling and challenging issues Sam has encountered and the solution to which has wide-ranging implications in any app that utilizes NSUserDefaults. At the end of this session, you will learn steps to avoid a devastating pitfall in Foundation.