It would be absolute godsend if we could, so one measly error wouldn't require restarting a entire process just to rewrite some small part.

That's really more erlang's niche.

I meant more like dynamically re-evaluating specific functions without having to restart the process. Haven't done much Erlang, but my experience is around doing so in lisp rather, which definitely can do that.

No, that's really Lisps thing.