Adafruit ATECC608 Breakout Board - STEMMA QT / Qwiic

You've got secrets, and you want to keep them safe? Most microcontrollers are not designed to protect against snoopers, but a crypto-authentication chip can be used to lock away private keys securely. Once the private key is saved inside, it can't be read out, all you can do is send it challenge-response queries. That means that even if someone gets hold of your hardware and can read back the firmware, they won't be able to extract the secret!