I enjoyed this a lot, it's short but I appreciate it because it was satisfying to play. The controls are good, the graphics and sound are good (although I'm not a fan of "rotating" big pixels but I give it a pass here) and I like how it has an ending that wraps the story. Only thing I'd maybe change is adding some animation for the zombies when they die instead of having them disappear but that's okay. Great work!
Edit: Oops I didn't realize this is still a WIP. Well this is a great start cause it already feels like a "complete" game despite being so short. Looking forward to the updates.