I chose to use prolog to essentially build an expert system across and heterogeneous data ecosystem.

Prolog could certainly use some serious improvements to its tooling. But the language is simple enough that it doesn't prove too much of an issue. You can get some much out of language it can be very powerful. In the system we've built it makes up a purely logical core that is completely referentially transparent, we leave all the ecky side effecting to a host program.