I will say that this game was a surprise. I played trough it and I found it nice, though I would want it to be longer, and I am hoping that you will add more levels into the game as it grows, that would just be fantastic to hear and see.
This game has three identifying features that I like about it:
1. The enemies that you encounter are hard, they are not so easy to kill at first, but bit by bit they get a bit easier, but they are still quite tough. Which is something I like. I hope to see more of the enemies that will come, and see how tough they are.
2. There is a big need of backtracking trough the game, you often have to back away, reload your guns, then come back in and do what you can. It's good to see that in the levels you are in, you always need a place where you can and need to backtrack to finish of your enemies.
3. You need to be clever in your play trough. My best strategy in the game is to shoot the enemies that I can with my weapon of choice, and if I run out of ammo in the clip, and don't have time to reload, I can switch to my other weapon that has a lot more ammo in the meantime, then back away, reload and do it again. Even using the grenades is quite clever of a tactic.
I also love the voice acting in the game. Quite fantastic for an early access game. The character feels a bit stiff though in movement, I would also like to see some other survivors that are alive and work as NPC's that can fight along with you.
All in all, I give the game 8/10
Good job guys! Hope to see more!