Yaron Minsky @yminsky.bsky.social · 11/06/2026I've been telling people for 25 years that Jane Street is not interested in formal methods. No more! And we're actively hiring to form a new formal methods team! blog.janestreet.com/formal-metho...blog.janestreet.comFormal methods and the future of programmingI’ve been telling people for the last 25 years that Jane Street as an organization was just not interested in formal methods. 38119
Yaron Minsky @yminsky.bsky.social · 29/03/2026Also: - optimized geospatial foundation models w/OxCaml - Live coding environments for teaching - Crazy time-travelling shells - Agentic software vigilantes It just doesn't stop... 062
Yaron Minsky @yminsky.bsky.social · 29/03/2026This is a fairly wild post about OxCaml Labs from @avsm . It's hard to summarize the stuff they're doing, but, some examples: - Some wild vibecoding - A formal semantics for package managers - A decade of docker containers (including OxCaml!?!) anil.recoil.org/projects/oxc...anil.recoil.orgOxCaml LabsOxCaml Labs 3274
Yaron Minsky @yminsky.bsky.social · 26/03/2026There's this... GitHub - janestreet/ppx_type_directed_value: Get [@@deriving]-style generation of type-directed values without writing a ppx · GitHub share.google/Q16s8YA9j0Rn...share.googleGitHub - janestreet/ppx_type_directed_value: Get [@@deriving]-style generation of type-directed values without writing a ppxGet [@@deriving]-style generation of type-directed values without writing a ppx - janestreet/ppx_type_directed_value 000
Yaron Minsky @yminsky.bsky.social · 20/03/2026If you're interested in hearing from someone who has this job now, I got to interview James Somers on Signals and Threads some time back: signalsandthreads.com/writing-tech...signalsandthreads.comSignals and Threads PodcastListen in on Jane Street’s Ron Minsky as he has conversations with engineers working on everything from clock synchronization to reliable multicast, build systems to reconfigurable hardware. Get a pee... 061
Yaron Minsky @yminsky.bsky.social · 20/03/2026Another fun hiring spot at Jane Street: we're looking to hire some great hybrid writers-and-engineers. As we grow and do more, communication becomes ever more important, for both internal and external audiences. www.janestreet.com/join-jane-st...janestreet.com 2121
Yaron Minsky @yminsky.bsky.social · 17/03/2026Anyway, it was a great conversation. (and maybe our longest episode yet?) I hope you enjoy! 440
Yaron Minsky @yminsky.bsky.social · 17/03/2026It was a really fun epsiode to record! Will is incredibly sharp and we had a really wide-ranging conversation, from the CAP theorem to the Lyappunov exponent of the Linux kernel (which is really a lot higher than I would have guessed) to the history of property based testing. 161
Yaron Minsky @yminsky.bsky.social · 17/03/2026And you can find it at the regular place here! signalsandthreads.com/why-testing-...signalsandthreads.comSignals and Threads PodcastListen in on Jane Street’s Ron Minsky as he has conversations with engineers working on everything from clock synchronization to reliable multicast, build systems to reconfigurable hardware. Get a pee... 120
Yaron Minsky @yminsky.bsky.social · 17/03/2026It's been a minute, but, time for another Signals and Threads, this one with Will Wilson about the testing tools he's building at @antithesis.com. And, in a bow to modernity, we have a video version of this one too! youtu.be/F_LvzcdNH3Q?...youtu.beWhy Testing Is Hard and How to Fix ItYouTube video by Jane Street 2110
Reposted by Yaron MinskyTy Overby @tyoverby.com · 08/03/2026A poor craftsman blames his tools. Wealthy craftsmen also blame their tools. Lots of tool-blaming going around. 0224
Yaron Minsky @yminsky.bsky.social · 05/03/2026Using Base and our PPXs, it looks like this. Still more verbose than would be ideal, but avoids polymorphic compare, which is an anti-pattern. blog.janestreet.com/the-perils-o... 010
Yaron Minsky @yminsky.bsky.social · 03/03/2026Anyway, fast deflation is pretty weird in monetary contexts. I really wonder what it would do to software engineering. 010
Yaron Minsky @yminsky.bsky.social · 03/03/2026I wonder if we're starting to hit a deflationary era in software engineering. For the first time, we're starting to talk about this in a planning context; it can make sense to put off some projects because we expect they'll be easier to achieve in the future than today. 200
Yaron Minsky @yminsky.bsky.social · 03/03/2026I wonder if we're starting to hit a deflationary era in software engineering. For the first time, we're starting to talk about this in a planning context; it can make sense to put off some projects because we expect they'll be easier to achieve in the future than today. 100
Yaron Minsky @yminsky.bsky.social · 03/03/2026I wonder if we're starting to hit a deflationary era in software engineering. For the first time, we're starting to talk about this in a planning context; it can make sense to put off some projects because we expect they'll be easier to achieve in the future than today. 100
Yaron Minsky @yminsky.bsky.social · 03/03/2026I wonder if we're starting to hit a deflationary era in software engineering. For the first time, we're starting to talk about this in a planning context; it can make sense to put off some projects because we expect they'll be easier to achieve in the future than today. 100
Yaron Minsky @yminsky.bsky.social · 03/03/2026I wonder if we're starting to hit a deflationary era in software engineering. For the first time, we're starting to talk about this in a planning context; it can make sense to put off some projects because we expect they'll be easier to achieve in the future than today. 170
Reposted by Yaron MinskyJoe Cutler @alphaconvert.bsky.social · 09/02/2026Seems like a good time as any to say I'm: (1) moving to New York next week, where I'll: (2) be writing OxCaml at Jane Street! Excited to start the next thing :) 2541
Reposted by Yaron MinskyNew Ideas in Networked Systems @nines-conference.org · 31/01/2026February 10th, and thus the inaugural edition of NINeS is just around the corner. You can participate from anywhere in the world, at times that are convenient to you. See nines-conference.org/attend for information on how you can participate. We hope to see you on Feb 10th!nines-conference.orgAttending NINeS 2026 066
Yaron Minsky @yminsky.bsky.social · 18/12/2025My regular PSA that if you enjoy working on developer tools, then Jane Street is kind of an amazing place. Apply here! There's no special posting, so just apply for the Software Engineering role, and express your interests in dev-tools in a note. janestreet.com/apply 0172
Yaron Minsky @yminsky.bsky.social · 23/10/2025So, if you're an experienced educator who loves working with new type-system ideas, apply! I think this is a really unusual and high-impact opportunity to combine those two passions. 120
Yaron Minsky @yminsky.bsky.social · 23/10/2025My hope and expectation is that approaching this with an educational lense will influence not just how we teach, but also the design of our tools, our libraries, and the language itself. 150
Yaron Minsky @yminsky.bsky.social · 23/10/2025You can actually see some of the great work from that group on Rust, in a talk Will recently gave at Jane Street: www.janestreet.com/tech-talks/r... 182
Yaron Minsky @yminsky.bsky.social · 23/10/2025We're hoping to work more with Greg as well as @shriram.bsky.social and @tonofcrates.bsky.social at Brown, and that some of their insights of thinking about how well designed tools and documentation can help people make the key conceptual leaps. 110
Yaron Minsky @yminsky.bsky.social · 23/10/2025The last couple of weeks have given us a sense of the scale of the challenges here! It was awesome having Gavin Gray, who came to the systems with fresh eyes, driving a tutorial on OxCaml at ICFP. conf.researchr.org/details/icfp... 120
Yaron Minsky @yminsky.bsky.social · 23/10/2025And more about OxCaml itself on oxcaml.org, where you can see some of our efforts to make this stuff easier to understand. There's a pile of documentation, including a tutorial on data-race free programming in OxCaml: oxcaml.org/documentatio... 120
Yaron Minsky @yminsky.bsky.social · 23/10/2025You can find the job postings here, for both NY and London: www.janestreet.com/join-jane-st... www.janestreet.com/join-jane-st...janestreet.com OxCaml Educator :: Jane StreetJane Street is a quantitative trading firm and liquidity provider with a unique focus on technology and collaborative problem solving. 201
Yaron Minsky @yminsky.bsky.social · 23/10/2025We've had an exciting couple of weeks full of opportunities to teach people about the exciting (and mildly bewildering) features of OxCaml. And...we're looking to hire an experienced educator to help us in this work. Please share this with anyone you think might be a good fit! 1184
Yaron Minsky @yminsky.bsky.social · 20/10/2025And please share with anyonhe else you think might be interested! 000
Yaron Minsky @yminsky.bsky.social · 20/10/2025One highlight at the end is a skech of the crazy new language features we're going to have to teach to the 100s of JS devs. If that sounds like an exciting challenge, consider applying! We have roles in both NY and London. janestreet.com/join-jane-st... janestreet.com/join-jane-st...janestreet.com OxCaml Educator :: Jane StreetJane Street is a quantitative trading firm and liquidity provider with a unique focus on technology and collaborative problem solving. 143
Yaron Minsky @yminsky.bsky.social · 20/10/2025I did anothr version of my "Saga of Mulicore OCaml" talk, but this time, nerve-wrackingly, the authors of the original paper were all there! Here's the link to the talk, which is found towards the end of the recording for the whole session. t.co/FQTmsFWji0 1232
Reposted by Yaron MinskyKit Eason @kitlovesfsharp.bsky.social · 03/10/2025Most companies be like “We daren’t go functional, we might not be able to hire”. Jane Street be like “Hold. Our. Beer.” 192
Yaron Minsky @yminsky.bsky.social · 03/10/2025And if you want to learn more about OxCaml itself, take a look here: oxcaml.org 020
Yaron Minsky @yminsky.bsky.social · 03/10/2025We're going to be at SPLASH/ICFP in Singapore, so if you're going, come talk to us! Richard Eisenberg is an especially good person to ask, but a lot of us will have useful context on this. 120
Yaron Minsky @yminsky.bsky.social · 03/10/2025Excited to say that we're looking to hire someone to focus on OxCaml education! We're doing enough to change the language that we have a pretty big internal education task ahead of us, and we want to hire someone to focus on it! Please share this with others! www.janestreet.com/join-jane-st...janestreet.com OxCaml Educator :: Jane StreetJane Street is a quantitative trading firm and liquidity provider with a unique focus on technology and collaborative problem solving. 1176
Yaron Minsky @yminsky.bsky.social · 30/09/2025A fun talk about...hacking OCaml. Basically, what you get when you supercollide a systems-y OCaml developer and a CTF. www.youtube.com/watch?v=SV9V...youtube.comHacking OCamlYouTube video by Jane Street 0194
Reposted by Yaron MinskyRichard Primus @richardprimus.bsky.social · 18/09/2025On Advisory Opinions, Sarah Isgur and David French speak with me about enumerated powers. The segment begins 43-44 minutes in, depending on format. This was a good conversation among people with different approaches to constitutional interpretation. thedispatch.com/podcast/advi...thedispatch.comThe Oldest Constitutional Question | Interview: Richard PrimusOriginalism through the lens of sola scriptura. 032
Reposted by Yaron MinskySimmo Saan @sim642.eu · 16/09/2025They should know the difference between TeX and LaTeX, so they could hate Lamport less and Knuth more. 111
Yaron Minsky @yminsky.bsky.social · 16/09/2025Clearly, the reason for the AI work is to build an AI capable of porting from Latex to Typst. 0120
Reposted by Yaron Minskya ton of crates @tonofcrates.bsky.social · 16/09/2025"we need a manhattan project for AI" no what we really need is a manhattan project for porting every math TeX package to Typst (and please start with mathpartir) 0212
Yaron Minsky @yminsky.bsky.social · 16/09/2025I should get them to read the part time parliament, and see what they think of Lamport then. 030
Yaron Minsky @yminsky.bsky.social · 04/09/2025Actually, maybe it's the only game in town if you want any two of those three properties... 000
Yaron Minsky @yminsky.bsky.social · 04/09/2025I'm pretty excited about the possibilities with Mojo, and I think more people should check it out. If you want a language that is pleasant to write in, that lets you write speed-of-light kernels, and lets you write kernels portably, it's kind of the only game in town. 120
Yaron Minsky @yminsky.bsky.social · 04/09/2025I think it's a great approach, and it turns out that it's something we're doing in OxCaml as well (though it hasn't quite hit production yet.) And you can see some early work in this direction with dialects like MetaOCaml: okmij.org/ftp/ML/MetaO...okmij.orgMetaOCamlIntroduction to BER MetaOCaml: how to use, how to install, the current status and the future development 110
