Can you review my Lisp implementation?

I’m learning OCaml the last few weeks, and following some Twitter friends I decided to build a simple Lisp implementation using OCaml. They call it Milho and it’s simple with a very lightweight core.

I did not finished the implementation yet, but I’m seeking to some feedback about my code and some design decisions. I am kind of alone on this, so I don’t have anyone to give some feedback.

My repo GitHub - renatoalencar/milho-ocaml