Current status of the compatibility is[1]:

> ~95%, closing the last gaps

If coding with LLMs taught me anything, it’s that this last 5% can be “load-bearing”.

[1]: https://github.com/eval-exec/neomacs#status

Most state is buffer-local rather than global. Note also that there is already some amount of multi-threading in elisp.

One thing you could imagine is doing some kind of mvcc system so that if two tasks don’t interfere with each other, they can execute in parallel (and if not, abort one and rerun it sequentially).

But maybe that still doesn’t work because all the things that should be run concurrently are using the same buffer and doing manipulations of it. You could imagine trying to make save-excursion introduce an opportunity for parallelism: split into a separate thread for the body as that thread is no longer modifying global cursor state (in some sense). Don’t let two threads write to the same buffer for concurrent tasks that should appear sequential, but do allow them to read in parallel (surely most things are merely reading).

However I’m not sure you actually need all that cleverness. I think you could have some combination of:

- tools to make multithreaded elisp more viable

- manual attention to improve major sources of slowness by introducing parallelism (eg font-lock, rendering, autocomplete, indentation). A stupid thing could be precomputing (in the background) what would happen in the user pressed RET (or TAB) and then being able to execute it sooner if they press that key.

>I'm huge into Emacs and have felt like Emacs has needed a Neovim sort of moment

That happened before with Xemacs. I saw somewhere Xemacs development has been restarted.

Appears to be further along than anybody's ever gotten with a multi-threaded emacs port. If that's what vibe coding gets us, three cheers for vibe coding!

I no longer see an issue with that, assuming it can be tested to prove it works. In this case, it's being tested (or well, claims to be) against real Emacs, which should be all that's needed.

"Emacs, rewritten in Rust — unleashed on the GPU, fixing what 40 years of C never could."

general issues aside, for me one of the issues with emacs is that for historical reasons there is a cut between elisp and C that's really high up and pretty ragged. ideally a large composable lisp project like emacs would have a very accessible continuum between the surface and the underpinnings.

so I don't think one can achieve that by maintaining 100% compatibility. a much smaller base system build with better semantics that was notionally compatible would be something I would be really excited to contribute to.

It's ironic that a community that uses a program originally developed at the MIT AI Lab, extensible in the traditional programming language of AI, would hate AI.

Richard Stallman prefers to call AI "Pretend Intelligence".

https://github.com/SimHacker/moollm/blob/main/designs/PRETEN...

Richard Stallman proposes the term Pretend Intelligence (PI) for what the industry calls “AI”: systems that pretend to be intelligent and are marketed as worthy of trust. He uses it to push back on hype that asks people to trust these systems with their lives and control.

From his January 2026 talk at Georgia Tech:

https://youtu.be/YDxPJs1EPS4?t=641

"So I've come up with the term Pretend Intelligence. We could call it PI. And if we start saying this more often, we might help overcome this marketing hype campaign that wants people to trust those systems, and trust their lives and all their activities to the control of those systems and the big companies that develop and control them." — Richard Stallman, Georgia Tech, 2026-01-23. Source: YouTube (full talk) — "Dr. Richard Stallman @ Georgia Tech - 01-23-2026," Alex Jenkins, CC BY-ND 4.0; transcript in video description.

I'm interested in a multi threaded emacs.

This landing page made sure I lost interest in this attempt.

JFC, who wants animations in their editor?

Also, I set prefers reduced motion on my browser. Pages that are filled with useless animations in spite of my preference tells me the dev is either incompetent as they cannot handle basic accessibility or an asshole because they just don't care.

I feel like we need some version of "increase the temperature" that works at a macro scale instead of on individual tokens.

The README is actually much better. Before AI it was three sentences or a placeholder template and you were complaining how nobody writes decent documentation. Now that the README actually describes what the project is all about you don't read it because "it's AI slop".

Sponsor button works though ;-)

It's not nonsensical, but if you were writing emacs in rust, you hopefully would use a typed language instead of elisp

> I've wanted an excuse to try out emacs in the first place[...]

This isn't the excuse - just try Emacs! I've gone through periods where I really wanted to level-up my $EDITOR-fu, and just jumping in is what I did. Compared to so many other decisions, this is such a low-barrier, low-cost decision, there's no reason to not just do it. If it's stalling your development speed, jump back to vi or VSCode, or whatever. Don't want to stick with Emacs? Uninstall and forget it was ever there.

For my editor explorations (vi, emacs, ex), I was strict with myself and used $EDITOR exclusively for 4 or 8 weeks (I forget which) - which sometimes just turned into years.

I'm not deep into Emacs culture these days, but I'm hard-pressed to understand why one wouldn't just go canonical GNU Emacs rather than some fresh "revolutionary" Emacs - you'll have your mind blown regardless, without the potential bugs and lack-of-history/community which come with some new-hotness interpretation of a standard that is already fit-for-purpose.

Please just try out traditional Emacs, I'm not sure this will paint a fair picture.

the "performance" link at the top also doesn't lead anywhere...

Lem's focus seems to be on being an "emacs" in and for Common Lisp. Lem throws away any attempts at compatibility with GNU Emacs.

This is trying to be compatible with GNU Emacs.

what's wrong with elisp? The runtime is really well integrated in Emacs! Note: AI is good at writing all lips dialects!

Emacs-ng embeds JavaScript or TypeScript or something and a web engine for UI. But then I really don't see the point. You're just about halfway to Visual Studio Code, so why not just use that?