Nice work! Lem looks "Spartan" at first glimpse, the high expansibility however is a promising key for success. Anyone who truly loves Common Lisp has the opportunity to make Lem the best Lisp editor ever.

I am a long-term Emacs user but I think we really need an optional editor which can be extended in Common Lisp rather than Emacs Lisp. What I really like about Lem is the KISS principle ("Keep it simple, stupid") since Lem is based on curses which is good for portability.

I have no experience with Roswell. Is it possible to use QuickLisp packages? Or do you consider to switch from Roswell to quicklisp? That would make installation of Lem much easier!