Calls, puts & mise en place

Appel & Mise

Vol. ITuesday, September 22, 2026 · 63° & patchy rain on the UWSThe daily, for Jeremy Ettlinger

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The lede

AI coding has made CI a bottleneck, so we reworked ours to keep up

Mufeez Amjad, Linear · made the Sunday

Linear's test suite nearly quadrupled since January and is still taking on roughly two thousand tests a week, which is what agent-speed code generation does to the one part of the pipeline that did not get faster. The write-up is unusually specific about where the minutes actually went: third-party runners with better CPUs bought 34% (tsc alone dropped 52%), the change-detection gating job came down from a 26-second median to 8, preinstalled dependencies and a narrowed monorepo install cut per-shard setup by 44%, and batching saved about 87,000 runner-minutes a month. The headline number is almost comic — six minutes of PR wait became just over five — until you notice the counterfactual, which is that the same suite would now take eleven. This is the shape of the next two years of infrastructure work for anyone whose engineers ship with agents.

AI & Agents

Simon Willison

Jev introduces a new shape of LLM — System One, aka decision models

Unstructured state in, typed probabilistic decisions out: you send a state object and a question, and you get back a float rather than a sentence — a 0-to-1 confidence, a probability distribution over choices, or a score on a scale you describe. Output tokens are free because there aren't any, and input runs $0.042 per million, which makes the classification layer of an agent loop nearly free to run and very cheap to evaluate exhaustively. Willison's caveat is the one to carry: a number with no tokens behind it is a black box with no reasoning trace to audit, and he demonstrates it scoring Cupertino high and East Palo Alto low without ever saying why.

Tim Dettmers

Frontier AI on your own hardware

The numbers are the argument: a 125B model on a single 24GB desktop card, a 550B DeepSeek on a MacBook with 128GB, and Qwen 35B at 450 tokens a second on 1.5 bits per weight. The auto-compaction work is the part most relevant to anyone running long agent sessions — sessions into the millions of tokens, a few past a hundred million, at roughly half the cost, from a method Dettmers is blunt about being simpler than the ones it beats. His broader claim, that an academic lab with no cluster can now work on things frontier labs skip, is testable in a way most renaissance claims aren't.

Engineering & Leadership

Colin Breck

I don't want to read what you didn't write

Breck's complaint is not about quality but about what the generated document leaves out — a design doc that describes what was built and never why, a pull request exhaustive on mechanics and silent on risk, urgency and what the author was worried about. The uncomfortable half is that the missing context is exactly the part the author was supposed to have thought through, so the document that skips it is evidence, not just prose. His proposal is narrow and usable: write it yourself, then hand it to the model as a ruthless proofreader and fact-checker.

Web & Product Craft

Dominik Picheta, Cloudflare

Python Workers are now generally available

FastAPI, Django and Flask now run on Workers without JavaScript glue, via WSGI and ASGI adapters sitting directly on the request rather than behind a web server, and the team implemented socket syscalls on top of the Workers connect API so ordinary database drivers work inside the WebAssembly sandbox. The genuinely interesting move is PEP 783: rather than maintaining a private fork of the wheel ecosystem, Cloudflare has proposed PyEmscripten as a standard so native-extension packages cross-compile for everyone. If you already deploy to Workers, this is a second language on the same edge with the same bindings.

New York & the Table

Jessy Edwards, Hell Gate

Governor Hochul now thinks NY may need a kill switch for AI

A year after watering the RAISE Act down to something closer to California's, Hochul is floating shutdown authority for models in an emergency, and the state has stood up an Office of Digital Innovation, Governance, Integrity and Trust with a Fordham law professor as deputy director. The mechanism is undefined, which is the story — a kill switch implies a thing with a power cord, and nobody drafting this has said what gets switched off, by whom, or how you would know it worked.

Gus Saltonstall, West Side Rag

Three weeks after a health department closure, the UWS Sweetgreen closes for good

Roaches in late August, a brief reopening, and then a sign on the door at 311 Amsterdam sending you eleven blocks to Columbus Avenue. The comment thread does the reporting the press release won't: neighbors describing an infestation that was the building's rather than the tenant's, which is the quiet reason storefronts on this stretch turn over faster than the rent alone explains.

Diversions

Literary Hub

John Green gives himself permission to suck

A short questionnaire pegged to a new novel, and worth five minutes for the working method rather than the book: his answer to being stuck is that nothing written today survives into the final draft anyway, so the day's pages cost nothing to get wrong. The better line is about rereading as instrumentation — the text holds still, you don't, and the delta is the only direct measurement of how you've changed that anyone gets.

Loose Change

Alex Chalmers, Works in Progress · made the Sunday

Why Arab armies don't win wars

Reviewing Kenneth Pollack's Armies of Sand, which sets out to explain a strange and consistent record — Egypt in 1967, Syria stopping at a broken Israeli line in 1973 to finish executing the plan, Libya losing to Chad — and spends most of its length ruling explanations out. Not the weapons, which were often the same ones their opponents used well. Not Soviet doctrine, since Cuba and North Korea ran the same centralized system competently. Not politicization, because Egyptian performance stayed poor after the officer corps was professionalized. What's left is organizational culture: tactical initiative punished rather than rewarded, information flowing up only in the shape superiors want, and one survey in which ninety percent of senior managers judged their subordinates unqualified to innovate. It is a book about armies that reads, unavoidably, as a book about what any hierarchy does to the people three levels down from the decision.

The Back Page

Andrew Beasley, The Guardian

Long-range hits and goals galore: inside the Premier League's return to chaos

Scoring is up from 2.75 to 2.82 a game, which on fifty matches is noise — except that in four of the last five seasons the rate climbed by at least 0.21 over the remaining fixtures, which would put this season second-highest in the Premier League era. Beasley's mechanism is the good part: teams running further, set-piece goals in decline, and shots from distance going in again, which together describe a league that has stopped trying to control the game and started trying to win it.

The Guardian

It's bordering on exploitation — how pseudoscience is duping football

Claire-Marie Roberts, running performance at Coventry City, was fielding up to fifty LinkedIn pitches a week for devices and supplements, including a caller who opened by asking how much oxygen is in the atmosphere and closed by offering to sell her some in a can. Her subject is the cryotherapy chamber and everything like it — expensive interventions with almost no evidence behind them, bought because the marginal-gains story is easier to sell to a board than the boring things that actually work.

Around town

Tue Sep 22 · 6:00pm

Future of Financial Services, with Microsoft AI

BrainStation, 136 Crosby St, SoHo

Free, and the useful version of this panel is the one where someone from the compliance side is in the room — financial services is where AI deployment meets the people whose job is to say no, which is the constraint his own industry runs on.

professional

Sun Sep 27 · 10:00pm, also Fri Oct 2 · 3:45pm

Oedipus Rex (Pasolini, 1967)

Metrograph, 7 Ludlow St, Lower East Side

Pasolini's first film in color, which opens in prewar Italy and then relocates Sophocles to a desert that looks less like antiquity than like someone else's planet. Franco Citti plays a man undone by not knowing the one thing everyone watching already knows, and the costumes alone are worth the late hour.

casual

Sun Sep 27 · 5:15pm

Ryuichi Sakamoto | Opus, with a Q&A

Metrograph, 7 Ludlow St, Lower East Side

Sakamoto's last performance, shot in black and white over eight days, with the cinematographer and producer there afterward to talk about how you film a man playing a piano for two hours without the camera becoming the subject.

casual

Tue Oct 6 · 11:00am

Brooklyn Tech Expo: FALL4AI Edition

26 Bridge St, Dumbo

Twenty dollars and a daytime room full of people demoing things that are not yet products, which is a different and better sample than the evening panels.

professional

Quote of the day

“I just give myself permission to suck.”

— John Green

On this day

September 22, 1985 — the finance ministers of five countries sit down at the Plaza Hotel on Central Park South and agree to talk the dollar down, which mostly worked, and which is the last time a currency moved that far because a room said so.

The puzzle corner

The Mini · Wordle · Connections

The Linear post and the Breck post are the same story told from opposite ends: the machine made the writing cheap, and everything downstream of the writing is now the expensive part.