Project Mentat is a persistent, embedded knowledge base. It draws heavily on DataScript and Datomic.

This project was started by Mozilla, but is no longer being developed or actively maintained by them. Their repository was marked read-only, this fork is an attempt to revive and continue that interesting work.

I imagine that a questionably-lively fork of an abandoned Mozilla project, which is not in Crates.io or Lib.rs, will not be a high priority to audit, but it appears to have only one piece of unsafe code — implementing an unsafe trait method that it doesn't appear to use — except where it exports its API for non-Rust consumers, which naturally has much unsafe.