https://www.youtube.com/watch?v=D7rlJWc3474 https://github.com/ekmett/guanxi

My understanding is he is using ideas from propagators and other places to make a performant logic programming framework in Haskell.

"a common knowledge base, the "blackboard", is iteratively updated by a diverse group of specialist knowledge sources, starting with a problem specification and ending with a solution. Each knowledge source updates the blackboard with a partial solution when its internal constraints match the blackboard state. In this way, the specialists work together to solve the problem"

I can't see the term Blackboard used in the paper. Probably irrelevant but just an observation.

[0] https://en.wikipedia.org/wiki/Blackboard_system

Unlike what is explained OP, the computation is one way.