Making a step aside but the nyxt browser is built on commonlisp and gives an emacs UX for browsing + hackability. It's not an editor but it's a recent user prog

Making a step aside but the nyxt browser is built on commonlisp and gives an emacs UX for browsing + hackability. It's not an editor but it's a recent user programmable common lisp system. And who knows, maybe they'll embed a live editor in it.