It was written in GLBasic, and I guess it was my own engine. I did try to get it on Steam back when I developed it, but they turned it down, saying it wasn’t the sort of thing they wanted on there platform !
They are way more open now. A possible catch is there is a $100 fee to publish a game (you get it back after $1K in sales of the game). That can be a barrier for many games that are usually on itch... Since it is GLBasic, looks like a Mac version would be possible as well. Do you have a Mac by chance?