It's very smooth, and I like the artwork. I didn't come across anything dangerous in the game, and tried shooting at the ammo and (I'm assuming) health pickups before I figured out what they were. I assume enemies are yet to be added?
The controls are a bit too responsive, I could hardly control the ship precisely and often found myself flailing about between each edge of the screen.
I couldn't initially run it because there were issues with filename case-sensitivity. I fixed it and submitted a pull-request for your approval.
Keep it up :) I enjoy retro space-shooters, I used to play one when I was a kid (forgot it's name now unfortunately, and I really miss it!). Looking forward to see how this one unfolds.