I went to see this game on Steam’s newest release tab, but the surprise (besides a nice affirmation that it sits at Very Positive reviews at this time) was realizing that it didn’t come from Electronic Arts or Ubisoft.
The article is technically pretty old now, but adds more details that have been made a lot more relevant on the game’s release.
And the engine work is a lot of extra development time added on, because it can’t be done concurrently with much of the later game design work.