Nice, a fun take on the loop theme. Looks and feels very pleasant. Cheers for having a linux build as well.
Some small details I think you could improve:
The first few levels were a little too easy in my opinion. I think you were trying to introduce each additional mechanic in its own level (so 1 level where you have to sequence 2 loops, 1 level where you overlay them, one where you have to use the empty entry, etc.). I guess it's better being too easy than too hard, but the sequences weren't that complicated so I don't think that amount of tutorial was really necessary. The game was intuitive on its own already.
Another thing I noticed is that once you put the correct loops into the sequencer, the game just immediately jumps to the next level. I think it would be nice to play the full sequence at least once before advancing, to give it a little bit of a celebration.