This jigg is for programming Supermini NRF52840 (https://github.com/joric/nrfmicro/wiki/ALternatives).

Print without support.
The holes might be very tight when printed and will need a sharp object to punch through especially the first layer which might be printed solid.
I used a sharp soldering iron to punch the bottom layer.

Put pogo pins through the holes. Solder wires to the pogo pins.
I only used the two middle holes (CLK and DIO). Powered the supermini through USB. Used a nRF52840-dk to program it.

Credit goes to my son, Linus who measured and designed it and it worked on the first try!