Liked the concept of the game, loosing lives while shooting. Game feels clean, music is cool, tutorial straight and clear.
Just a little things that might help You in the further development I noticed. When there is a diagonal movement, You move fast.. (quick fix: if You move diagonally, move to the two directions * square root of 2).
And when switching to a different weapon other than pistol, I was not able to switch back with the 1 key.. (might have just been pressing a wrong key (using macOS))
Allover a really cool game, as I said I like the concept of it.. not being forced to kill a monster to go through the level.
Great coding, Jacob.