Hello, I played this game a few days ago - it is in a very nice and polished state, congratulations :)
I liked the level design in general, although there is a very steep spike in difficulty somewhere around level 10-12 if I remember. I particularly liked the level in the screenshot because if you fail any of the first jumps you can retry them, rather than always starting the level over. I think that would be a nice thing to add to some other levels, sort of as ad-hoc checkpoints that you can get to and try the next part several times, for example.
I see you can push ESC and go back out to the main menu, but that is not clear at all. Maybe you could consider adding a button to click on to bring up the pause menu as well?
In general, the aesthetic, the theme, and the overall feel is very good. Sometimes there are spikes which felt hard to see and a little unfair as a result. the 1-bit graphics are great and I love them, but maybe something could be done to increase the visibility of spikes, especially when they are next to some grass tiles.
The jump itself feels a little unpredictable, almost like the gravity is too much, or the whole game speed is just too high. I think it would feel more fair if the downward acceleration started a little slower, so you had just a little bit more time at the top of the jump to determine if you needed to make another jump or not.
Thanks for sharing this project, it is very well done :)