Rather than having to solder a serial adapter to the chip to flash it, [Ryan] came up with a slick 3D printed programming jig that uses pogo pins. If you have to program these boards in bulk ...

Luckily, all it really take is some stiff metal wire, a rod, and patience. Unless you’ve got a 3D printer, that is. In which case, we’d suggest you print out this very clever “Spring Factory ...