Will this have steam support?
So far, it has no overlay support, due to the way the launcher works. I hope this gets fixed.
As for Steam support itself, it's not on Steam nor Greenlight. I think they plan on doing everything themselves, which is unfortunate for us users but hey, a fun game is a fun game.
Edit: Seems you can run the game without the launcher, allowing you to use the overlay, however, the game will not update this way.