"You shot yourself 111 times." You'd think I'd know better by now.
So I have a few notes. Its a shame the health restoration and bullet damage doubling is only in the description, it could have done with an in-game tutorial. The health meter seems to be under the player, as I've found out on the last wave when I decided to stick myself into a corner. A bit more enemy variety could have helped with the optimal strategy being to shoot every new slime with the exact right amount of bullets as soon as it arrives. I ended up maxing out my health before buying any other upgrade, and the slimes were still never any danger to me. The upgrade shop not pausing the game or clearing out the bullets did cost me a fair chunk of health though :]
On the positives side, the graphics look neat and its very clear what's happening at all times. Music's a good fit (at least far as I can tell, audio is a mystery to me). The shop offers enough upgrades that there's room for multiple playstyles, for example creating a deadly wall of bullets in the path of future slime only to inevitably have to dodge it myself instead made for an exciting strategy. Most importantly, it's clearly fun enough that I got to the "survive" wave, died to bouncing bullets into my own face, and started another run anyway.
I think what's there is a fun way to kill ten minutes, and with a few tweaks there's a fair bit of potential for more.