Very clean, very polished in terms of graphics. Gameplay is super fluid too, albeit a slightly bigger shuriken would be better so they wouldn't keep barely missing those birds, but you can chalk that one down to just me being terrible.
The downside is the sound design. It sounds like it's trying too hard to be the stereotypical console retro with the buzzsaws and the overly bitcrushed voice. Let off the gas on that a little.
Otherwise it's great, can't wait for the full version.