It's not exactly what you're looking for but you might be interested in Lem[0]. It's an emacs-style editor but written completely in Common Lisp on top of curses/SDL2. I haven't used it that much (same for Emacs itself, really), but it looks like a very solid foundation
Does look interesting, in the meantime I've been hooked on Zed which has users building support for missing Vim features, they claim their goal isn't to 100% emulate Vim functionality, but I would not be shocked if it just winds up having most if not everything most people like about Vim fully baked in.
[0]: https://github.com/lem-project/lem