Currently, I've only implemented as far as the tutorial provides. Some future work includes running from files (currently only supports a REPL) and more stuff in the stdlib. However, I'd like to do a reimplementation using Rust as well as learn more about programming language compiler and interpreter implementations.
Some topics I'm interested in include types (so I'd need to work through some set -> group -> category theory math before I get there.) and learning Haskell or ML(OCaml/StandardML).