The big news here is that Racket now can run threads in parallel. While there were ways to get parallelism before (like places), this is much more lightweight and familiar. Anything that expands the areas where Racket is viable is good news to me since I like writing stuff in Racket.

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ModernMech 2 hours ago | parent [-]

I feel like version 9 just getting parallel threads kind of contradicts the homepage when it says Racket is "Mature" and "Polished".

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kryptiskt an hour ago | parent | next [-]

It's not at all strange, Python and OCaml are mature and polished and they still have tackled the same issue very recently.

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spdegabrielle 2 hours ago | parent | prev [-]

This is addressed in the blog post linked from the release announcement: https://blog.racket-lang.org/2025/11/parallel-threads.html

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ModernMech 27 minutes ago | parent [-]

That post is even more worrisome!

> To address larger problems with the implementation and to improve performance, we started in 2017 rebuilding Racket on top of Chez Scheme. Rebuilding took some time, and we only gradually deprecated the old “BC” implementation in favor of the new “CS” implementation, but the transition is now complete. Racket BC is still maintained, but as of August 2025, we distribute only Racket CS builds

So they're billing Racket as "Mature Practical Extensible Robust and Polished". Of those I will give them "Extensible" and "Robust". You can't say you're mature and polished and practical if you've just rewritten the entire thing and deprecated the legacy codebase to support new features that have been in other languages since forever.

Maybe they were talking about Racket 8.0 and didn't change the website yet?

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nesarkvechnep 23 minutes ago | parent [-]

How rewriting something internally makes Racket not mature? Sounds like refactoring to me and with an extensive test suite there's nothing to be hysterical about.

	▲	ModernMech 9 minutes ago \| parent [-]
		Maybe I just have a different working definition of these words. To me "mature" means "fully developed" and "polished" means "achieved a high level of refinement". Rewriting it all to introduce a major feature that fills in a longstanding hole in the language doesn't say "mature and polished" to me. Because often times many bugs are introduced into a codebase on a major rewrite despite extensive test suites. Typically people might prefer a mature codebase to one that's just been rewritten precisely because it hasn't been vetted over years. "mature rewrite" sounds like an oxymoron to me, and I guess no one else agrees but I find it strange. That is all.