I absolutely love the idea of embedding Prolog-esque rules inside a full traditional programming language for solving specific problems. The region-based local mutation is also an incredible idea that would really solve one of my core pain points with immutable languages like Haskell and Elixir.

Also this part made me let out an audible "wow":

> We can exploit purity reflection to selectively use lazy or parallel evaluation inside a library without changing the semantics from the point-of-view of the clients.

Will definitely keep an eye on this language! The syntax seems a little odd (inferring type parameters for functions?) but I'm sure I could get used to it.