It was really fun, unfortunately it only had one level ;-;
With some more levels this can definitely become a really cool game, the use of assets to make the ships was really interesting.
Something that doesn't seem quite right is that, in fullscreen mode at least, you can move your ship to the sides of the screen, I'm almost sure you can't receive damage if you're there since it seems like bullets dont reach you, but you can still shoot. It made it way too easy to defeat the boss, especially with the sideways shoot upgrade.
As you can see, I'm at the left of the screen haha.
Other than that, I don't think I found any problems. It's one of the best games I've played of the jam, I really enjoyed it.