Coalton can be used wherever (almost any) Common Lisp can be used: mixed in, side by side, exclusively, as an library, etc. CIEL doesn't presently ship any nat

Coalton can be used wherever (almost any) Common Lisp can be used: mixed in, side by side, exclusively, as an library, etc. CIEL doesn't presently ship any native Coalton interfaces, so all invocations of CIEL within Coalton code would have to be in a "lisp" form, which is like Rust's "unsafe". (define (some-coalton-function arg) ;; break out to Lisp (lisp String (arg) ...CIEL stuff here...)) On ordinary safety settings, the String declaration on the Lisp code will be checked at runtime so that wrong types don't leak back into the surrounding/calling Coalton code. Conversely, Coalton code can be freely used within Common Lisp code regardless of whether it uses CIEL.