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janmidtgaard.bsky.social
Recovering academic. Occasionally hacks OCaml and property-based testing, manufacturing bad luck on an industrial scale. Mastodon account: https://types.pl/@jmid
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Last night it was announced that our TACAS-paper 'Dynamic Verification of OCaml Software with Gospel and Ortac/QCheck-STM' co-authored with Nikolaus Huber, Naomi Spargo, Nicolas Osborne, and Samuel Hym won the 2025 @etapsconf.bsky.social's Best Tool Paper Award 🎉 #testing #pbt #award

There are people I know in the national security community who are terrified that the US government is sleepwalking into a 9/11-level catastrophe. Focusing finite resources on nonsense like this instead of credible threats -- that is the reason they're so worried. www.wsj.com/world/greenl...

Oooh, MirageOS+unikraft PR has appeared from @tarides.com, which should allow much easier deployment of OCaml code to the @unikraft.cloud ! github.com/ocaml/opam-r...

A blogpost I wrote on elm-test's Test.Distribution - testing whether your fuzzers generate interesting cases often enough! martin.janiczek.cz/2025/05/01/e...

This video was posted on Twitter by the official account of the People's Republic of China's embassy in the United States. The Chinese Communist Party is lecturing the US Republican President by using a Reagan speech on the importance of free trade. We are really living in the Weird timeline.

👀 Oleg Kiselyov's compilers course in OCaml 👀 okmij.org/ftp/tagless-...

...and the award for best exception name showing up in an opam-repo CI run goes to... 🏆😄

≪We estimate the supply-side value of widely-used OSS is $4.15 billion, but that the demand-side value is much larger at $8.8 trillion. We find that firms would need to spend 3.5 times more on software than they currently do if OSS did not exist.≫ From www.hbs.edu/faculty/Page... #opensource

Scratching another old itch, I've utilized a wonderful hack by @edwintorok.bsky.social to get the Thread-modes of Lin and STM working much better 🤓 github.com/ocaml-multic... (as in: from defunct to decent) It even works on OCaml 4 too! 😄

If all goes well, OCaml 5 code will ride into space in < 24 hrs. www.dphispace.com/post/parsimo...

> We have been using OCaml 5 in production since the middle of February 2025, and the rollout has been entirely uneventful. This was a highlight for me, after having worked to stress test it over the past ~3 years. There are other nuggets in @semgrep.bsky.social's latest blog post though... 🤓

Great work from @tarides.com folks on pragmatic verification of OCaml software. Chosen as one of the distinguished papers at TACAS 2025. Paper: janmidtgaard.dk/papers/Huber... Code: discuss.ocaml.org/t/ann-ortac-...

Finally - Relocatable OCaml in “fully relocatable” mode is also reproducible (as long as the C compiler is reproducible) and passes its testsuite 😮‍💨🥳🎉🍾🎊

Dear all After a bit over 3 years my contract with Tarides has come to an end. It has been great - working with and being team lead for an exceptional group of software engineers and - applying my property-based testing skills to stress test and help get the multicore OCaml5 runtime+stdlib in shape.

Raphaël Monat has a PhD position open to work on static analysis with him at Inria in Lille 🙂 recrutement.inria.fr/public/class... #phd-position #abstract-interpretation #static-analysis #ocaml

Beautiful morning in Aarhus for a morning dip with 4C water and 3C air ☀️🌊🤓

QCheck(2) hacking continues: 💻 github.com/c-cube/qchec... Replacing an RNG split hack with faster, gastly Obj.magic one, QCheck2 on OCaml 4 starts to work reasonably 🤓 #ocaml #quickcheck #pbt

I got Linux running in a PDF file using a RISC-V emulator. PDFs support Javascript, so Emscripten is used to compile the TinyEMU emulator to asm.js, which runs in the PDF. It boots in about 30 seconds and emulates a riscv32 buildroot system. linux.doompdf.dev/linux.pdf github.com/ading2210/li...

Over the past couple of days, I've been scratching a 3-year old QCheck(2) itch github.com/c-cube/qchec... It's nice to finally make progress on it! 😃 #ocaml #quickcheck #pbt #fp

If you wanted no leaks you should have gone into Settings -> Security -> Configure privacy & security -> Privacy options -> Other -> Configure -> Media interface and clicked “Disallow.” The Leak setting is on by default but we understand your privacy is important so we’ve made it easy to opt out

A post about the long and winding road that lead to the Dune build system for OCaml, and, eventually, to Dune replacing our old internal build system, Jenga. blog.janestreet.com/how-we-accid...

Yesterday a very good friend gave me this nice box of homemade OCaml coasters, all 3d-printed. Naturally, they were immediately put to good use... 😄🍻 #ocaml #fp

I'm really happy to present, with @tarides.com , #OCaml Eglot, an #Emacs (minor) mode for editing OCaml code, using LSP through Eglot, the built-in #LSP client of Emacs: github.com/tarides/ocam... Feedback, contribution and RT much appreciated

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TIL that multicoretests has entered Debian tracker.debian.org/pkg/ocaml-mu... and Arch('s user repo) aur.archlinux.org/packages/oca... 😮🎉 #ocaml #pbt #quickcheck #fp

Published a blog post about cram tests (fancy snapshot tests) in dune. It's a bit of a tutorial style and showcases a feature I truly like about dune. Hope you like it! sancho.dev/blog/cram-t...

I've written up part 2 on our effort to utilize property-based testing to stress test the OCaml 5 run time system. Happy Christmas reading! 🎄🎅 🎁 😄 tarides.com/blog/2024-12... #ocaml #pbt #fp #functionalprogramming #quickcheck