The mechanics are seriously amazing and the levels are interesting too.
The character controller feels a good bit too floaty which the level design doesn't use at all, so it is just there ending up as something you gotta get used to. It isn't really much more floaty than the mario series, however I would recommend staying less floaty than those games unless you specifically wanna use that floatiness.
The other critique I have is that it is just too short. I know that's a given for jam games, but that results in the mechanics just being hard to get used to. you could've thrown in a few very easy levels just to introduce the base mechanics (if possible by time of course). And furthermore I just really liked the levels the game had and would've enjoyed more of them (to be honest maybe only if the floatiness and next point were fixed).
Another personal annoyance are the Keybindings, they are so scattered around it gets physically annoying to do. I personally am used to moving with the arrow keys and having z/yxc as action keys. That seperates action from movement with your hands and doesn't leave the thumb pressing the spacebar, which is just located far away from the other buttons and can feel really bad to press depending on keyboard.