The controls work well, and the gameplay is decent, but overall this feels like an experiment in coding rather than a true game. It just isn't fun, to be honest. The lack of puzzles, obstacles, enemies, or a point at all, coupled with the random-seeming backgrounds and non-coherent platforms (blocks, hills, clouds...and more blocks), just make it seem experimental.
As an experiment, it is perhaps notable that sliding down walls looks exceptionally awkward once you are almost at the bottom of a wall, because you are still using the "flush against a wall" frame but you're now "flush against the air" which looks strange.
Also, most games that allow double/triple jumping also allow it when you fall. This game doesn't. You don't get a double jump unless you did your first jump. I don't know if that was intentional, but it feels awkward.
I highly recommend taking the game/physics engine of this, getting a decent level designer and some plot, and releasing an actual game with fixes to the sliding and jumping. This could go far, but as is it's not much of a game.