It was fun to read this because I happened to study at Indiana University where most of the work on *Kanren happened.
If anyone is interested in practical applications, Will Byrd (mentioned in the story) went on to work with Matt Might (HN's favorite CS-prof-turned-doctor). One of the products of that was mediKanren[0] which operates over medical research. There was some publicity around mediKanren last year.[1]
[0] https://github.com/webyrd/mediKanren [1] https://www.uab.edu/news/health/item/10703-diagnosis-in-2-12...