Glad you enjoyed it! All games I make is just a small hobby thing I do on my spare time, so I have no plans on ever charging for it.
Recent community posts
Well Aseprite is only for the graphics when I do my pixel art, the actual engine itself is made by me, and it depends on very little. The reason for going with my own engine is that it's a lot of fun to make things yourself, and I want to program in C++ so Unity and the likes have never really interested me. My current engine is somewhat similar to Unity, but made for 2D pixel perfect graphics and allows you to do all your work in C++, even scripts, which is awesome.
I started a Linux port of the engine some time ago, and got pretty far, but then I kind of lost interest and felt it was better to continue making the actual game instead, so I put it on hold. It's definitely something I want to do at some point in the future, especially so I can get things more easily running on Mac.
As the source is available here https://github.com/darkbitsorg/db-08_green_grappler, a Linux build should not be that hard to make if you want to. As I currently do not really have a proper Linux installation, I cannot supply one at the moment.