I’ve read about this. They basically reverse engineered how USPS creates the unique tracking number.
They aren't hard to generate. They give you how to generate them via their own documentation. It's just made up of an app ID, service type code, mailer ID, serial number, and check digit.
alt Hacker News
They aren't hard to generate. They give you how to generate them via their own documentation. It's just made up of an app ID, service type code, mailer ID, serial number, and check digit.