Scryer Prolog aims to become to ISO Prolog what GHC is to Haskell: an open source industrial strength production environment that is also a testbed for bleeding edge research in logic and constraint programming, which is itself written in a high-level language. Scryer Prolog passes all tests of syntactic conformity, variable_names/1 and dif/2. The homepage of the project is: https://www.scryer.pl

