I thought maybe interesting for you guys.
Here the link, where I found this:
https://pod.asap-soft.com/posts/2463041
This arcade platformer is very likely the first Game Boy title to be developed in a 100% libre environment, and that goes for both code and assets.
Originally released in...
I really want this, even though the price is quite steep :(
Can someone please dissuade me from buying one of these?
https://www.retromodding.com
https://www.freeplaytech.com/product/freeplay-cm3-diy-kit/