Slava Pestov

Programming languages, finitely-presented monoids, horses

Pronouns: he/him
Homepage: https://factorcode.org/slava
Generics: https://download.swift.org/docs/assets/generics.pdf
Monoids: https://monoids.net

Public Key

npub1t2kv4pt2hyxhasmrjswwr94vchdd7cq8msn336mtdfgulqxdtqkse82wfh

NIP-05 Address

slava_at_mathstodon.xyz@momostr.pink

Profile Code

nprofile1qqs94tx2s44tjrt7cd3eg88pj6kvtkklvqracfccad4k55w0srx4stgpz3mhxue69uhhyetvv9ujuerpd46hxtnfduqs6amnwvaz7tmwdaejumr0dsh5yg5e

Publishing to

relay.nostr.band

relay.damus.io

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Author Public Key

npub1t2kv4pt2hyxhasmrjswwr94vchdd7cq8msn336mtdfgulqxdtqkse82wfh

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Last Notes

2026-10-13 23:50:02 UTC

Sam Altman is upset someone left a recording device in his conference room. I guess he forgot to explicitly opt out of data collection for marketing and training purposes

2026-10-10 02:54:20 UTC

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I think proving decidability essentially means you have an algorithm that always terminates, even if it’s impractical to actually execute. Now is it possible to encode a proof of decidability in a way that allows someone else to verify the claim without revealing the algorithm? Probably but I have no idea!

2026-10-09 19:56:20 UTC

RE: https://mathstodon.xyz/@davidradcliffe/117412692476120189
How about monoids with word problem solved (artisinally), then?
#note1x6n…dt2g

2026-10-07 15:27:11 UTC

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The “I need to design my own programming language -> operating system -> CPU -> VLSI CAD system -> programming language” doom loop

2026-08-24 23:10:56 UTC

Forget about programming languages suited for writing compilers and whether that’s good or not, how about a programming language specially for implementing other Turing-tarpit languages in the most concise way possible. There’s a lot of diversity between, say, lambda calculus and Brainfuck. What abstractions would you pick for your language, and why?

2026-08-15 16:49:10 UTC

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System 7 was a local optimum in GUI design I think. I always thought the Platinum appearance that came after was driven by marketing trying to look “modern” compared to Windows and Motif, than any functional benefit

2026-08-15 16:45:13 UTC

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I must admit I haven’t found time to look at your work more closely, but I have to say the GUI theme is on point

2026-08-07 07:56:52 UTC

RE: https://recurse.social/@lindsey/116938013465737693
“Haskell attracts idealists who care about correctness and think carefully about the abstractions they build with. Hiring for a Haskell role has never been the problem that leaders think it will be. If anything, candidates came to us for the Haskell itself, even when they had no particular interest in supply chain.”
#note1r8p…vyd0

2026-07-01 15:30:39 UTC

Smalltalk-80, HyperCard, and Visual Basic 6 were far more compelling "future of programming" attempts than anything available today

2026-06-26 18:28:19 UTC

Perl 5 LLM policy
https://perl.topicbox.com/groups/perl-core/Tded84d01cb16966e-M4f2b94e0c07f9d7cb8e1e76b

2026-06-25 00:15:28 UTC

RE: https://social.nouveau.community/@andnull/116807799779378492
An interesting corner of PL history saved from bitrot, thank you!
#note1z5w…tue0

2026-06-23 15:57:58 UTC

Open source projects will tell you they have no choice but to allow slop, because doing anything else is a form of gatekeeping that will exclude too many potential contributors.
Nothing could be further than the truth, though. When the review queue is a non-stop machine gun of giant, bogus drive-by patches, the good contributions will inevitably fall through the cracks.
Eventually, the contributors you actually want—those who care about the long-term health of the code base, building institutional knowledge, improving their craft, mentorship—will simply leave, because they will realize their limited time and energy is better spent elsewhere.
A blanket ban on LLM contributions is not impractical, idealistic, or too radical—it's just common sense.

2026-06-02 23:49:13 UTC

Collatz semantic versioning: pick some integer to be your first version number. If it’s even, divide it by two to get the next version number, otherwise multiply by three and add one. When your software reaches version 1, proclaim it to be finished.

2026-05-28 16:19:46 UTC

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Delete 2; a -> bc, b -> a, c -> aaa

2026-05-22 16:21:57 UTC

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There is a legitimate need for safe(r) systems languages that give you precise control over memory, because there are still plenty of problem domains where something more dynamic can’t really work. But definitely I agree that the search for the “C++ successor” has sucked the oxygen out of the room in the language design space, feels like a fad at this point

2026-05-09 17:55:53 UTC

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How about a smalltalk dialect where classes and methods are files and the browser is built on top of filesystem metadata queries

2026-05-05 23:42:32 UTC

This article is about the software bug. For events occurring during the presidency of George W. Bush, see Presidency of George W. Bush.
https://en.wikipedia.org/wiki/Bush_hid_the_facts

2025-12-28 04:27:51 UTC

I’ve always wanted an IBM mainframe! My brother-in-law gave me a LEGO z16 for Christmas. Check out the hot pluggable CPU
https://media.mathstodon.xyz/media_attachments/files/115/795/296/780/815/417/original/357d30128422b820.jpeg
https://media.mathstodon.xyz/media_attachments/files/115/795/296/788/151/950/original/979558a3315eeaf8.jpeg
https://media.mathstodon.xyz/media_attachments/files/115/795/296/787/958/353/original/b8ab660bdb684a27.jpeg
https://media.mathstodon.xyz/media_attachments/files/115/795/296/761/842/397/original/e8f2851078130703.jpeg

2025-11-23 00:24:27 UTC

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Wait, does overleaf use its own TeX implementation that’s not TeX?

2025-10-30 12:14:04 UTC

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Knuth 4A also spends a bit of time on the “majority” operation which takes three booleans and returns the one that appears at least twice