Fun and engaging, really solid. You had a lot of cool ideas how to put more variety into those levels.
I liked the level design a lot, it was always clear to whether I'm supposed to go somewhere or not, can I make this jump or is it too far. Also it's nice that in a puzzle platformer like this the jump has fixed height, so the restarts due to spikes are always consistent.
I wish that there was a way to implement all those mechanics (attaching/letting go/boost, etc.) without mouse and using only the keyboard, but that might just be me.
The music got a little bit repetitive after a few levels, but you made it yourself, so that counts for something ;)
Anyways, great job!