i love the theme and the sounds, and i had a couple ideas where you could improve game feel.
it seems the game adds boost speed relative to the player's current momentum. this is most noticeable on green candy canes, where falling onto one gives you much less boost than jumping up into one. it may feel more reliable to zero out the player's momentum when they collide and then add the boost value to it. (you may have to tweak the values)
the blue candy canes work great if you're holding a direction but act very strange if you jump into them from neutral. you could probably change this the same way by zeroing the player's momentum on collide and then setting the player's speed to the boosted value you want, the rest of the boost control feels great.
big fan of your game and always excited to see another platformer, great job :)