Works ok on GNU/Linux openSUSE 42.1 64bit with Radeon R7 250X using Mesa 11 drivers.
btw: I couldn't find any controls to exit the game apart from alt+f4 :-P
Chill, so far so good, it's really ok as it is now. Just add some visual feedback on what is happening.
I killed everything, became a semi-bird, started flying, reached space, the score counter overlapped after 9999... Is there anything more? :-)