DK Alpha release by Lasse Honnens & art by Flemming Schmidt.
Penguin with a Pumpgun
Inspecting the files It seems to be developed in Monogame (With it's XNA history). Haha.. actually first I thought it was an XNA project. XNA was discontinued by Mircosoft in 2013. But the Mac and Linux versions indicated something else was up.

So it turned out to be Monogame. Not something we see often in DK.
Free open source multiplatform framework here
https://www.monogame.net/
Just gave it a spin.. it starts out brutally hard and nothing is explained. So be prepared for a few tries before completing the first level. A bit of onboarding the player a smoother difficulty curve would be recommended for future versions.
There are also numerous other issues.. so keep that in mind, it's still very early days for this project.
Penguin with a Pumpgun ALPHA DEMO
Penguin with a Pumpgun ALPHA DEMO on itch.io (Windows, Mac, Linux)
https://lassehonnens.itch.io/penguin-wi ... alpha-demo