Mark Dominus

I'm looking for work, please boost! I'm a software engineer with 35 years of experience. I've worked across an unusually wide range of domains: mobile game backends, privacy-preserving data platforms, high-throughput COVID testing infrastructure, email and account systems, e-payment processing, job marketplace systems, and bioinformatics. I pick up new domains quickly and have a history of doing it repeatedly. I understand how to turn business needs into engineering requirements. I prefer to work remotely but I am open to an in-office job in the Philadelphia area or especially in Philadelphia itself. I've often worked remotely since the 1990s and can operate with minimal supervision. Several of my favorite projects were self-directed: I identified the need, built the thing, and shipped it. My preferred time zone is America/New_York, but I'm flexible. Some of the many, many technologies I've used are: Python, Perl, TypeScript/JavaScript, Haskell, Go, C, Java. Postgres, MySQL, SQLite. Flask, SQLAlchemy. AWS (Lambda, S3, RDS, SQS, EC2). Docker, Git. Github and Gitlab. I've also repeatedly picked up new languages and stacks as needed: Haskell for differential privacy research, TypeScript for a 24/7 AWS Lambda system, Flask for my most recent employer. I've become productive with new systems over and over, and I can do it quickly. I'm a published author (Higher-Order Perl, Morgan Kaufmann), longtime blogger, and conference speaker with a reputation for making complex ideas clear. I am a U.S. citizen. My résumé is at https:// plover.com/~mjd/cv/Mark%20Jason%20Dominus.pdf mjd@pobox.com Thanks! #OpenToWork #remoteWork #softwareEngineering #Python #backend #hiring#fediHire #getFediHired

This is the most exciting technical thing I've seen this week. Stephen Diehl has built an algebraic effects language, #prism , that might actually be usable. I've been excited about algebraic effects since Bauer and Pretnar's 2012 paper. Haskell's stacks of monad transformers always looked to me like a first-generation hack: yes, we have the technology that could fix the Awkward Squad, but we don't know yet what to do with it. Algebraic effects seemed like they could be the way forward. But I tried programming in Eff and found it impossible to make _anything_ work. Even if Prism isn't practical for practical programming, it's a big step forward, and worth a look just for the ideas. #haskell #algebraicEffects #programmingLanguageshttps://www.stephendiehl.com/posts/prism/

“We report the unexpected discovery that octopuses possess structurally unique ribosomes that enhance the accuracy of protein synthesis compared with ribosomes from all other tested animals.” https://www.biorxiv.org/content/10.64898/2026.06.25.734654v1.full #octopus

“Prediction markets are ‘truth machines,’ in the sense that they give people incentives to figure out what is true and bet on it. But they are also, obviously and increasingly, falsehood machines, in the sense that they give people incentives to make bets and then distort reality to make those bets pay off. Because of prediction markets, it is now lucrative to figure out what song will be the most popular, but it is even more lucrative to make a different song look most popular. Prediction markets can make it harder to know what is true.” (Matt Levine)

Here's one reason why birthright citizenship is important in the USA. Suppose my citizenship is questioned. Mine specifically, I mean. The government wants to deport me, detain me without trial, take away my voting rights, or prosecute me for being in the country illegally. I have an easy answer to this. I produce my birth certificate, which says that I was born in New York State in 1969. They confirm this with the New York State Department of Health, and that is the end of the matter. Without birthright citizenzship, with the regime that Alito and Gorsuch want, it's *not* the end of the matter. The government can look at my birth certificate, scoff, and demand that I prove my parents were here legally. And they can imprison me until then. Okay, but I can prove that they were here legally. After all, they were citizens from birth. I produce my parents’ birth certificates, showing that they were born in New York State in 1939 and 1943 respectively. Do you see where this is going? But that's not good enough because without birthright citizenship, just being born in the USA is not good enough. I also have to prove that my grandparents weren't here illegally. And proving that my grandparents were U.S. citizens is not good enough. In fact my paternal grandfather was brought here as a child, 1913. Can I prove he was here legally? Perhaps his immigration paperwork contains a misstatement of fact, his naturalization was void all along, my father has been here illegally for 87 years, and I am subject to immediate deportation to Hungary or El Salvador or South Sudan. Without birthright citizenship, every person's status is in precarious.

@adapalmer@wandering.shop Bonus trivia: It is a coincidence that the names "wombat" and "numbat" sound similar. They are from unrelated languages spoken on opposite sides of Australia.

@phooky@hexa.club I have to say I find the phrase “cutting-edge penis” quite off-putting and not at all enticing.

@phooky@hexa.club Tempting, but mine is only a standard model and I'm not sure I know anyone with a next-generation penis.

Best Hacker News comment in a while: “Homeopathic medicine is already recommended by 1 out of 1000000000000000000 doctors.”

@LevendLichtje@mastodon.art I thought at first that you were recording your e-book reading by making full-size simulated books to put onto a full-size bookshelf and I was trying to figure out a way that that was not completely bonkers. I was relieved when I saw the cat.

I just flipped open my copy of "The Blue Machine" by Helen Czerski and the first sentence that fell under my eye was “It's not clear why whales should have earwax at all.” The whole book is like that. It's marvelous. https://bookshop.org/a/93187/9781324086345

Or maybe more briefly: When doing AI-assisted programming, it sometimes happens that people have the AI generate both the code and its tests, and then discover that although the tests pass because code and tests match, both diverge from the specification of what the AI claimed its code would actually do? How do we know this didn't happen with the 1.2 million lines of Lean that purport to be validating the solution to the Erdős unit distance problem? Couldn't they be a 100% correct verification of the wrong theorem?

@mattblaze@federate.social I was delighted to learn recently that in order to resign, a Member of Parliament needs the approval of the Chancellor of the Exchequer, approximately the equivalent of the U.S. Secretary of the Treasury. I learned the reason why: MPs are not legally allowed to resign; this dates from a time when it was a troublesome duty that many people wanted to avoid. So when a modern MP does want to resign, it is accomplished by having the Chancellor appoint them to a post under the Crown, and officers of the Crown are disqualified from serving in Parliament. One of the two obsolete posts they use for this legal maneuver is called the “Crown Steward and Bailiff of the Chiltern Hundreds”. Wikipedia has a list of its officeholders over the centuries which includes the eight who were all appointed on 17 December 1985, each immediately resigning the post to make way for the next appointee. I hope you found this note more amusing and interesting than annoying. (In practice, the Chancellor almost never withholds consent.) https://en.wikipedia.org/wiki/List_of_stewards_of_the_Chiltern_Hundreds

If Spice is required for interstellar travel, and is available only on Arrakis, how did humans get there in the first place?

@LevendLichtje@mastodon.art This is really fun! I'm glad you posted the picture with the cat, before that I didn't understand the scale, which is important.

@NanoRaptor@bitbang.social

1. XY Problem
2. (With @byorgey@mathstodon.xyz ) Burritos are monads.
3. Lightning talks

RE: https://sigmoid.social/@conitzer/116969360352975674 Conitzer confirms that this is not sarcasm or a joke. He gave ChatGPT 5.6 Sol a single 300-word prompt asking it to solve a not-too-difficult but open problem of game theory, and to write a paper about it. This it did, without further guidance, in 90 minutes. He describes the result as being top-quality undergraduate-level work: “I would have encouraged the student to work on it just a bit more to submit it for publication somewhere.” Ignore the name of the blog (“Funny AI Fails”). This isn't one.

“Isn’t it striking how many illustrations of a burning planet we see, and how few realistic images of just and sustainable futures we might be working towards?” https://buttondown.com/muledesign/archive/dodging-evitable-futures-together/

I had a good Claude success yesterday. I wanted a diagram to demonstrate Euclid's Proposition 36, that if you have two parallelograms between the same pair of parallels, and their bases are equal length, then they have the same area. I thought I'd try to use Desmos' geometry tool to draw this, but I couldn't figure out how to do it. So I went to Claude and told it to make an SVG of the diagram I wanted, which it did. Then I said to Claude “I tried to draw this in Desmos's geometry tool but couldn't figure it out. Can you walk me through that, if it's possible to do?” And it did, and — this is the big win — now I know how to do this with Desmos's geometry tool. People keep saying that AIs are going to make us less capable, but my experience has been the opposite. AIs have been excellent at helping me become more capable. https://www.desmos.com/geometry/oqgdt6e1p7

@MartinEscardo@mathstodon.xyz I once had Claude document a solution to a defect in software I was writing. Then I read over its notes, made corrections, and added: “# Approved-by” “Claude abstracted these notes from our discussions of the issue. Mark Dominus has read, reviewed, edited, and approved these notes.” Later, I asked it to write a similar set of notes for the solution to a different defect, telling it to follow the form of the first set. It included the Approved-by section verbatim. 😡

I'm going to repeat this quote because it's worth repeating: “Imagine a flashy spaceship lands in your backyard. The door opens and you are invited to investigate everything to see what you can learn. The technology is clearly millions of years beyond what we can make.” “This is biology.” (Bert Hubert, quoted in “I should have loved biology” https://jsomers.net/i-should-have-loved-biology/ )

@halcy@icosahedron.website @shapr@recurse.social

@nash@labyrinth.social It's the secret that Big Container doesn't want you to know

@maj@cosocial.ca @mattblaze@federate.social I believe this is what we in the software business call “a temporary workaround”.

This slide from a Polish researcher spells “Fraïssé” correctly but gets “Łódź” wrong??¿? #icm2026

@Retreival9096@hachyderm.io @nash@labyrinth.social I just heard a report from an ADHD sufferer that it had been very helpful to get a hamper for the *clean* clothes. He couldn't get himself to fold up or put away the clean clothes, but he could throw them in the hamper, which kept them clean and kept them from getting mixed up with the dirty ones.

“[Saunders Mac Lane] began inserting a space into his surname because his first wife found it difficult to type the name without a space.” what?

I wonder if it really isn't clear why whales should have ear wax. I think the reason why humans have ear wax is: it prevents small insects from building nests in our ears. Any insect that tries will get stuck in the wax, die, and are eventually be ejected. Why wouldn't the same advantage accrue to whales? What else is there to prevent a whale's ear canals from being colonized by barnacles? But the ear wax solution seems like it would work.

“[Sir Thomas Browne's prose] is a monument to a brief enchanted period in the seventeenth century when English had achieved the whole range of its expressive powers, and when its greatest writers were not yet burdened by any bad conscience about employing those powers to their fullest.” (David Bentley Hart) https://thelampmagazine.com/blog/how-to-write-english-prose #thomasBrowne

Typo of the day: “Cod review”.

“I am not saying that it’s impossible for data centers to ever cause any problems with water. They require careful planning in the same ways other large industrial buildings do. What I am saying is that right now no reasonable forecasts imply that data centers will rise to become a significant problem for water access in the US. Almost all complaints about their national water use are basically just saying ‘We should not have a new large industry in America using water.’” https://blog.andymasley.com/p/the-ai-water-issue-is-fake

@ranjit@friend.camp I fell in love with this book and have it on my shelf right now. It's marvelous.

@nxskok@cupoftea.social I know the feeling. My OS comes with ł and Ł already set up, but I had to set up ő myself, and I get a little drop of self-satisfaction every time I type “Erdős”.

@phooky@hexa.club Taken literally, your suggestion surprises me. I would like very much for the US to develop large industries in manufacturing and installing wind turbines for example. And building e-bikes and producing plant-based foods. Are you serious in your opposition to all new large industries?

@jonmsterling@mathstodon.xyz I'm sorry if I'm being low-brained, but people did, in fact, make this argument about calculators in the 1970s and into the 1980s. So I think some answer is required. A different but similar example: When I was in first grade our classroom had acquired a cheap manual typewriter, which at the time was an unusual novelty. I liked practicing on the typewriter, but my teacher complained that I would be better off spending more time on my penmanship, which was a more valuable skill. Now, with the wisdom of hindsight, I can say: she was wrong.

@bth@infosec.exchange @pozorvlak@mathstodon.xyz Yeah, Claude says my theory is no good at all, for several reasons, one of them being that whales don 't have external ear holes anyway, and another being that they don't expel earwax, it just accumulates for their entire lifetime. I haven't checked yet if any of this is true.

@ricci@discuss.systems I've wanted to scream about this for a while too, and inspired by your post yesterday I tried it out right then. “Lorrie Kim" is a reasonable pick, that's my wife. Henry Reister was my boss at the job I was laid off from in June. I have SMSed him three times total, most recently in December 2025. I have never sent him a photo. "Great Dismal" is an ad-hoc folder for sending my kid photos from a vacation we took in March–April, 2026. I haven't opened it since. "New Years Eve 2025" is, yes, from December 31, 2024. Of course (610) 707-8983 is the real prize here. What, I wondered, would it turn out to be?

@barubary@infosec.exchange “[It] settles the main questions I asked about and then some”.

Why did early ASCII have ← and ↑ but not ↓ or →? https://retrocomputing.stackexchange.com/q/30618/6644

@vnikolov@ieji.de Is your point that the slide is written in English, and the English name for Łódź is “Lodz”?

@phooky@hexa.club Are there other large industries would you like to eliminate? UPDATE: I would like to withdraw this question, which I think is not to the point.

@nxskok@cupoftea.social Yeah, I was wondering about that too. I'd expect both to have the Ł or neither.

RE: https://mathstodon.xyz/@pozorvlak/116965638671616359 “If the model knowingly is looking for vulnerabilities in order to escape, and this does not even surprise you all that much, something has already gone terribly wrong, and you know what you should expect when the models get smarter.”