The movement system in your game feels really fluid! That's fairly uncommon for a lot of itch platformer games and is pretty exciting to see.
I noticed a blind-spot: would strongly suggest implementing coyote time and input queueing mechanics to your jump, as it felt very hit-or-miss when running towards an edge (especially noticeable in the sandbox). If you plan to have much platforming in your project it's going to be a source of frustration as-is.