Fun game and interesting concept!
Overall it's very well made and polished, but something about movements are a bit off. Sometimes I gain a lot of unexpected speed (like when I start climbing a wall) and sometime I lose momentum and I'm not sure why XD Technically speaking I feel like there are some interaction that are not working as intended. Other examples are the stomp that sometimes give you an air jump, and the basic enemies that if you press space the frame you hit them make you do a super jump.
Despite that, the game is still very fun and I enjoyed it a lot. One thing that in my opinion you should remove is to have to kill every enemy to complete the level. When you go fast you usually skip some of them, and have to take care to kill them all slow down the player, while the best thing is to go as fast as you can without dying.