I am going to add a weak "not recommended" review, though I should be clear that that applies to the game's current state -- there is a ton of potential here, but due to some questionable design decisions I don't know if that potential will ever be realized. For reference, some of my favorite games are Gnomoria and Dwarf Fortress, though I did enjoy Terraria a lot.
First the good:
* Cute art and adorable dwarves.
* Detailed and interesting world design, though with very limited ecology.
* Deep and varied tech tree.
* Solid-seeming tech foundation for a builder/sim game.
* Ant farm full of dwarves!
* Terrible user interface:
* tons of superfluous click-and-drag for crafting -- it gives you the recipe but you still have to click and drag into a grid. Maybe for the first time but subsequently producing an item should be easy. Few games make me long for DF's UI.
* generally lacking polish -- highlighting items won't tell you what they are, meaning you spend time guessing what an icon/sprite means. You cannot speedup time and the game proceeds at a glacial pace, a 2/4/8x bar would be nice, especially in early game.
* obnoxious leveling system -- this is by far the worst part of the game. You don't tech up by building structures, doing research, etc, nor is the entire tech tree available ala Banished -- you tech up in two ways. By crafting 10 ladders you don't need so you can make torches, etc, and by "unlocking" recipes that are "locked" by earning XP -- yes, a builder game with XP grinding, like some casual Facebook game. this mechanic might be able to be kept in if improved, but as it stands it just makes the early game a boring, frustrating clickfest. And the game pauses while crafting, which compounds the already slow speed.
I know these sound like minor complaints, but taken together they really ruin what could be an enjoyable experience. This game has solid technical design and ideas, but I'm not sure where the authors are going with it; the concerns I mention raise alarm bells, for me at least.
I still got some enjoyment out of the game (not done playing yet), and it might be worth picking up on sale, but I really can't advise paying $15 in the current state. Maybe once the dev gets further along or the price drops.