Going into this I was wondering what kind of shovelware I was about to play, and then I instantly loved the game. The feel of running around and shooting the enemies felt great, music was going hard, and the crabs snapping their claws at me had me going.
The idea of making a game where the play space reduces was one of my first ideas, glad someone managed to make it work.
A little tip to improve the feel of the game further would be to buffer the shoot input. Since you have to click on time with the recovery, you sometimes press a bit too early, so buffering the input a tiny bit (maybe 100ms) would make you shoot anyway even if you clicked too early.
My first try I scored 50200!