Arnaud Spiwack
@aspiwack.bsky.social
Multi-classed Software Engineer/Constructive Mathematician. Sometimes plays video games sort of fast. Puts topoi in your computer.
Pinned
Arnaud Spiwack
@aspiwack.bsky.social
· Nov 17
👋 Welcome (numerous) newcomers.
I'm a Tokyo-based, French, polyglot software engineer, computer scientist, mathematician, and hobbyist speedrunner.
I generally speak of programming languages and their theory, linguistics, science, video games, movies, books. And how the world is very funny indeed.
I'm a Tokyo-based, French, polyglot software engineer, computer scientist, mathematician, and hobbyist speedrunner.
I generally speak of programming languages and their theory, linguistics, science, video games, movies, books. And how the world is very funny indeed.
Reposted by Arnaud Spiwack
I thought the notion of “sheaf for a Lawvere-Tierney topology” was a very complicated one, but I realized it's actually not so complicated, and it can be defined completely internally (i.e., you don't need to know what a topos is, just how constructive math works). •1/7
November 9, 2025 at 10:18 AM
I thought the notion of “sheaf for a Lawvere-Tierney topology” was a very complicated one, but I realized it's actually not so complicated, and it can be defined completely internally (i.e., you don't need to know what a topos is, just how constructive math works). •1/7
In fact, isn't a tail call technically have a function call?
Mmm 🤔 Is half a function application like half an A press?
November 8, 2025 at 12:51 AM
In fact, isn't a tail call technically have a function call?
An intriguing thing about Wasm is its treatment of control structures. Wasm proposes more structured than gotos, but less so that loops: lexical labels.
The idea is that labels are scoped, and jump instructions can only jump to an in-scope label. 1/3
The idea is that labels are scoped, and jump instructions can only jump to an in-scope label. 1/3
November 5, 2025 at 12:44 AM
An intriguing thing about Wasm is its treatment of control structures. Wasm proposes more structured than gotos, but less so that loops: lexical labels.
The idea is that labels are scoped, and jump instructions can only jump to an in-scope label. 1/3
The idea is that labels are scoped, and jump instructions can only jump to an in-scope label. 1/3
It was just an itemize environment with just text (no maths) in it. So nothing advanced. It still caught my eye. Done, appropriately, by a scientist. Though I am amused at the idea that Latex is one of the things that survived an apocalypse.
This must be how long it takes for inspiration to percolate.
On other news, Fire Force is the first time I saw someone typing some Latex in an anime. Tip of my hat to that. You win, Fire Force.
On other news, Fire Force is the first time I saw someone typing some Latex in an anime. Tip of my hat to that. You win, Fire Force.
November 2, 2025 at 11:54 PM
It was just an itemize environment with just text (no maths) in it. So nothing advanced. It still caught my eye. Done, appropriately, by a scientist. Though I am amused at the idea that Latex is one of the things that survived an apocalypse.
Kaiju #8 and Fire Force are two animés that I watched recently (and quite liked) which remind me, for different reasons, of Attack on Titan. They were started in 2020 and 2019 respectively. Attack on titan in 2009. By the time the anime started in 2013, its popularity was well established, I think.
November 1, 2025 at 12:55 PM
Kaiju #8 and Fire Force are two animés that I watched recently (and quite liked) which remind me, for different reasons, of Attack on Titan. They were started in 2020 and 2019 respectively. Attack on titan in 2009. By the time the anime started in 2013, its popularity was well established, I think.
Reposted by Arnaud Spiwack
things you can curry :
- dishes
- favors
- horses
- people
- software functions
- dishes
- favors
- horses
- people
- software functions
October 18, 2025 at 3:28 PM
things you can curry :
- dishes
- favors
- horses
- people
- software functions
- dishes
- favors
- horses
- people
- software functions
Reposted by Arnaud Spiwack
Reposted by Arnaud Spiwack
Il y a 2 ans, j'ai trouvé que j'avais pas assez de boulot, et j'ai fait un projet avec la classe de CP de ma fille. Chaque élève a imaginé pourquoi il n'avait pas pu faire ses devoirs, et je l'ai illustré. Après, ça a donné un petit livre qui a été distribué à chacun.
October 7, 2025 at 2:13 PM
Il y a 2 ans, j'ai trouvé que j'avais pas assez de boulot, et j'ai fait un projet avec la classe de CP de ma fille. Chaque élève a imaginé pourquoi il n'avait pas pu faire ses devoirs, et je l'ai illustré. Après, ça a donné un petit livre qui a été distribué à chacun.
Reposted by Arnaud Spiwack
October 6, 2025 at 9:22 PM
Streaming some Final Fantasy VI: Worlds Collide, in a few minutes. I'll be playing to the seed of the week, which appears to have a pretty unusual objective.
twitch.tv/notnotarnaud
twitch.tv/notnotarnaud
Twitch
Twitch is the world's leading video platform and community for gamers.
twitch.tv
October 8, 2025 at 12:16 AM
Streaming some Final Fantasy VI: Worlds Collide, in a few minutes. I'll be playing to the seed of the week, which appears to have a pretty unusual objective.
twitch.tv/notnotarnaud
twitch.tv/notnotarnaud
Reposted by Arnaud Spiwack
We just spent 6 months to add 1 figure to this paper. Some people said, "Couples aren't prioritizing men's careers. Men just have better earnings opportunities when moving."
Earnings effects of moves for couples on the left, singles on the right. Negligible gap between single men and women.
Earnings effects of moves for couples on the left, singles on the right. Negligible gap between single men and women.
October 7, 2025 at 3:36 PM
We just spent 6 months to add 1 figure to this paper. Some people said, "Couples aren't prioritizing men's careers. Men just have better earnings opportunities when moving."
Earnings effects of moves for couples on the left, singles on the right. Negligible gap between single men and women.
Earnings effects of moves for couples on the left, singles on the right. Negligible gap between single men and women.
I've had a look at Hyprland recently. I must admit that it looks like a quite attractive desktop experience. 1/4
October 6, 2025 at 3:06 PM
I've had a look at Hyprland recently. I must admit that it looks like a quite attractive desktop experience. 1/4
Questions à ceux qui sont en France. Quelqu'un peut m'expliquer comment tout le monde semblait savoir à l'avance que le gouvernement Lecornu allait démissionner immédiatement? D'où venait cette conviction?
October 6, 2025 at 9:29 AM
Questions à ceux qui sont en France. Quelqu'un peut m'expliquer comment tout le monde semblait savoir à l'avance que le gouvernement Lecornu allait démissionner immédiatement? D'où venait cette conviction?
In French, but this excellent article on the dangers of over-diagnosing makes the following striking claim: cancers that mammography detect are largely benign, whereas actual dangerous breast cancers tend to be invisible to mammography until it's too late. Bleak.
“Vous allez avoir beaucoup de réactions négatives de la part de vos lecteurs”, avertit une spécialiste du sujet. Car oui, il est sensible et compliqué. Alerter sur les risques des diagnostics médicaux semble aller à l’encontre du progrès, voire du bon sens. Nous vous laissons lire, vous jugerez…
Surdiagnostic médical : l’alerte
Les chiffres donnent le vertige : de plus en plus de maladies sont diagnostiquées inutilement, entraînant de nombreuses conséquences délétères. Médecins et chercheurs tentent de s’organiser.
www.epsiloon.com
October 6, 2025 at 12:52 AM
In French, but this excellent article on the dangers of over-diagnosing makes the following striking claim: cancers that mammography detect are largely benign, whereas actual dangerous breast cancers tend to be invisible to mammography until it's too late. Bleak.
Reposted by Arnaud Spiwack
Et voilà ! Pour ceux et celles qui veulent écouter mon petit passage sur France info junior sur les maths pour la fête de la science
www.franceinfo.fr/replay-radio...
www.franceinfo.fr/replay-radio...
Comment apprendre le goût des mathématiques ?
Alors que la Fête de la science se poursuit jusqu'au 13 octobre, les enfants de franceinfo junior s'intéressent aux mathématiques avec Viviane Pons, maîtresse de conférences en informatique à l'univer...
www.franceinfo.fr
October 5, 2025 at 6:33 PM
Et voilà ! Pour ceux et celles qui veulent écouter mon petit passage sur France info junior sur les maths pour la fête de la science
www.franceinfo.fr/replay-radio...
www.franceinfo.fr/replay-radio...
See you there!
@aspiwack.bsky.social will be presenting "Destination calculus: A linear λ-calculus for purely functional memory writes", joint work with Thomas Bagrel, at OOPSLA on Saturday 18th 2025.splashcon.org/details/OOPS...
Destination calculus: A linear λ-calculus for purely functional memory writes (SPLASH 2025 - OOPSLA) - SPLASH 2025
Distinguished Reviewer Awards This year, we had an exceptional Review Committee with over 100 RC members and 8 Associate Chairs. Nevertheless, several people in our group of AEs and chairs explicitly…
2025.splashcon.org
October 2, 2025 at 9:22 AM
See you there!
Reposted by Arnaud Spiwack
One of my favorite anecdotes from THE PREHISTORY OF THE FAR SIDE: "That doesn't sound like the Jane Goodall we know."
October 1, 2025 at 6:13 PM
One of my favorite anecdotes from THE PREHISTORY OF THE FAR SIDE: "That doesn't sound like the Jane Goodall we know."
Final Fantasy VI worlds collide stream in 15min 🙂
twitch.tv/notnotarnaud
twitch.tv/notnotarnaud
Twitch
Twitch is the world's leading video platform and community for gamers.
twitch.tv
October 1, 2025 at 12:15 AM
Final Fantasy VI worlds collide stream in 15min 🙂
twitch.tv/notnotarnaud
twitch.tv/notnotarnaud
There's a tension in operational semantics: big-step semantics are more expressive, but they're harder to reason about than small-step semantics.
More expressive because you can easily do some cleanup after evaluation. 1/6
More expressive because you can easily do some cleanup after evaluation. 1/6
September 27, 2025 at 2:34 AM
There's a tension in operational semantics: big-step semantics are more expressive, but they're harder to reason about than small-step semantics.
More expressive because you can easily do some cleanup after evaluation. 1/6
More expressive because you can easily do some cleanup after evaluation. 1/6
The “command palette”, the newest, hottest invention in UI. Is in fact at least as old as Emacs and Vi (that's the 1970s, for those in the back). It wasn't called that way, of course. Emacs's command palette even lets you enter entire programs.
September 17, 2025 at 7:45 AM
The “command palette”, the newest, hottest invention in UI. Is in fact at least as old as Emacs and Vi (that's the 1970s, for those in the back). It wasn't called that way, of course. Emacs's command palette even lets you enter entire programs.
An interesting feature of gendered language is that they have to decide, when importing a word from a foreign language, which gender it gets to be. Is a Gameboy “un Gameboy ” or “une Gameboy ” in French?
September 17, 2025 at 12:07 AM
An interesting feature of gendered language is that they have to decide, when importing a word from a foreign language, which gender it gets to be. Is a Gameboy “un Gameboy ” or “une Gameboy ” in French?
I came across the word “bullshittery” today. It's fascinating. Originally, of course, “bullshit” is a noun. Thanks to the (immense) flexibility of the English language, it was made a verb (it was verbed, as it were) “to bullshit”.
September 16, 2025 at 10:24 AM
I came across the word “bullshittery” today. It's fascinating. Originally, of course, “bullshit” is a noun. Thanks to the (immense) flexibility of the English language, it was made a verb (it was verbed, as it were) “to bullshit”.
This is a remarkably effective chart.
Time to break out the chart
September 14, 2025 at 2:22 AM
This is a remarkably effective chart.
Incorrectness logic is one fascinating point regarding how knowledge is formed. It wasn't technically difficult to come up with. In fact, it was pretty obvious, trivial even, anybody familiar with Hoar logic implicitly knew it existed.
September 12, 2025 at 2:20 AM
Incorrectness logic is one fascinating point regarding how knowledge is formed. It wasn't technically difficult to come up with. In fact, it was pretty obvious, trivial even, anybody familiar with Hoar logic implicitly knew it existed.
It's been quite a while, but I'm back to streaming today. Getting back into Final Fantasy VI: Worlds collide
Stream starts at 00.30 UTC twitch.tv/notnotarnaud
Stream starts at 00.30 UTC twitch.tv/notnotarnaud
Twitch
Twitch is the world
twitch.tv
September 10, 2025 at 12:11 AM
It's been quite a while, but I'm back to streaming today. Getting back into Final Fantasy VI: Worlds collide
Stream starts at 00.30 UTC twitch.tv/notnotarnaud
Stream starts at 00.30 UTC twitch.tv/notnotarnaud