On a couple of projects we figured that if a customer is motivated to break in to the device, they're welcome to whatever is there. That doesn't mean we made it

On a couple of projects we figured that if a customer is motivated to break in to the device, they're welcome to whatever is there. That doesn't mean we made it easy, but we didn't go out of our way to obfuscate things or erect barriers: There's SPI, there's the flash bus, have fun. We disabled the debugger that we had on the UART, though. We're not totally crazy. Just getting something working out the door is challenging enough. Firmware always comes in hot.