Intriguing project! I think you've settled on a useful set of tools as Rust can be embedded readily in another language or runtime system while still providing memory safety with a modern language features without dealing with C++ or impossible FFI scenarios. Personally I see the "X in Rust" of a lot of projects of late as a "oh I could be reasonably confident in building something solid on top of that quickly without shooting myself in the foot by messing up a C library API". It seems Rust provides a good ecosystem to implement reusable core primitives. I've been exploring how to use some simpler parts of Prolog/DatalSC in a library, which this project targets almost perfectly. Looking forward to reading how you implemented the core prolog algorithms!