Your file says it's for windows, linux and mac, but it's just a windows executable. I was able to get it running under wine though on linux.

Anyway, quite a nice game, very nice aesthetic, nice little chip tune and overall it works and feels quite good and polished! The only thing I'd mention is that the difficulty curve is quite steep and the game becomes very challenging before I'm able to collect enough coins to get much better weapons. I'm probably just bad at the game but still, there's a lot of enemies very fast and when they start shooting at me it's just overwhelming quickly :D Overall though, great game, great feel, great polish, great sound and great use of the asset ^^ nice