I was SO excited when I first read this article, as I was at the time implementing shared-global multithreading in a fork of JS Interpreter [1][2] and it was thrilling to think that we might one day have true parallelism in a real JS engine, not just simulated concurrency in our educational toy.

Since then I've often wondered if anyone at Apple was still working on this, or if it was just one of those things (like proper tail call support in V8) that was destined never to see the light of day.

A year or so ago I tried tracking it down again (apparently I'd not bookmarked it at the time) but alas several search engines responded only with a sea of articles about web workers.

Finally, last week I put Gemini on the case and, despite it claiming that it didn't exist and that I must be conflating memories of some other related articles it did correctly identify you as the author, after which it was easy to find the link to the original article on your blog.

Since re-reading it I've been wondering if it might be possible to implement it with help from AI (not having written any C++ since before the turn of the century I don't think I'd be too successful doing it unassisted!), or whether JSC's internals might have drifted too far in the intervening years.

It's delightful that someone else has take a stab at it, and I look forward to seeing where this leads.

Thanks for all the work you did laying the groundwork that made it feasible to even contemplate, then contemplating all tricky details and writing the answers down in the form of such an inspiring article.

[1] https://github.com/NeilFraser/JS-Interpreter [2] https://github.com/google/CodeCity/blob/fa1bd2734b806559ffaf...