[epolanski]

It is actually amazing, emacs is probably the best example of a "living" program you can modify interact and debug directly while you are coding it.

Obviously lisp has been designed around its REPL and debugging experience and the concept of "living programmable programs", but emacs reaches an insanely high level of business complexity, far higher than any software any of us probably writes at work and yet modifying and learning the very program you are using with the program itself is a 30+ years old solved problem that apparently ecosystems outside lisp dialects seem not to pick up.