Solvers are integrated into Prolog nowadays, like the other commenter said.
The real problem is that Prolog doesn't play nice with relational databases. (Too bad the people behind the short-lived NoSQL fad didn't know about Prolog, though.)
Smuggle a Prolog in YAML somewhere, call it YAMLogic or anything else really which can’t be directly traced to it and watch the kids be amazed at what you can make computers do.
Only about 33% serious here, but… still a bit serious.
The real problem is that Prolog doesn't play nice with relational databases. (Too bad the people behind the short-lived NoSQL fad didn't know about Prolog, though.)