Not all Lisp dialects have well-developed hot patching systems. The OOP system has to be carefully designed for it. What if a class definition is superseded by a reload, but there are existing instances? The Common Lisp dialect of Lisp has useful answers to questions like this, but not necessarily every Lisp you come across.

Even Bash supports hot-reloading. I've developed modules that are updated in place by sourcing:

   $ . /path/to/script.sh