A nice game! The music and art really matched well with the vibe of the game, and the gameplay itself was pretty smooth.
It took quite a bit of getting used to though: it presents like an endless runner (and you note it as such yourself), but the spacing of the blocks sometimes require more precision jumping, more like a platformer. The combination is probably quite interesting, harkening to the chase sequences in some platformers, though I struggled a bit (and it felt like the bullet sped up over time?).
Anyway, nice job!