I really liked this, good work!
I think it's a very interesting take on a classic tower defense sort of game, where the player also has to be a bit more active. I think it was neat that I had to avoid attacks while fixing my towers, it added a nice element of hands on gameplay. The entire game feels super polished! The visuals are great!
For suggestions if you work more on this, I'd say it'd be cool if you had some sort of indicator of where enemies will spawn next. Since you can't be everywhere at once, it sometimes feel like you don't exactly know where you should spend your scrap, and it feels really bad putting a tower somewhere to then realize there's a wave coming in the opposite direction. It would also be nice to have some tooltips for the turrets, since I forgot what each turret was when reading the description, lol.
Overall, great entry! Keep up the good work!