But of course, the bootloader has to be able to program the chip, so there’s got to be a way in. The trick is that [Majek] has carefully modified the Arduino’s Optiboot bootloader so that it ...

(Check the video below.) Aside from tiny-soldering skills, [Vinod] wrote his own custom bootloader for the AVR-based Arduino. With just enough memory to back up the AVR’s flash, the bootloader ...