This is amazingly well polished. The aesthetics are nice, the animations are smooths are the sound design is clean. The jump mechanic adds a nice twice to the classic platform type game.
The difficulty seems rather high for a gam jam, and the game is defintly resisting, but this is not a bad thing.
If I had to to find a point where it could be improved, it would be in way the theme fits in the game. The game is definitly heat-themed, with the lava and stuff, but the gamplay mechanics do not feel to be that much about "overheating".