Nice game!
When I tried your game. I had one tower in each row. At some point, one of the bigger zombies broke through. Since I had only generators left in that row, the zombie could just destroy everything here and get through and I lost. A bit unsatisfying because I couldn’t do anything. I just had to wait until it’s over.
Otherwise, I like the idea of curing zombies. I think I cured one before it was over. Also the day-night cycle looks quite nice.