>>106255654
Lem has potential because emacs only really has a single weakness: the single thread. Nothing else actually matters, modern elisp compilation even gets rid of most of the performance issues, but it can't escape that damned single thread.
After years of using emacs everything has always worked perfectly fine, except for the only issue: opening a big file or running a big program and the entire program freezing for several minutes and then possibly crashing, with no ability to do anything about it. Even for things which should in theory be separate processes, like lisp repls, somehow getting into an infinite loop means I have to kill the entire emacs server and restart it.

Ideally it wouldn't just be multithreaded, but multiprocessed and sandboxed with memory and processing time limits.