Great little game that is very thoroughly designed!
There's a few little odds and ends that could be improved, in my opinion, like a bigger player sprite, a clearer indication of the secondary upgrade trees and a meaningful downside to death, but none of those things really reduced my enjoyment while playing.
I love the details in the glitchy UI, the oxygen flask and the visual upgrades to the player suit and I dig the disquieting ending a lot (even though I wonder if I missed something without any credits rolling).
I'm definitely looking forward to more like this.