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Field notes on AI, data products, and spec-driven development, with detours into Formula 1, economics, and life
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An American Team on an American Sunday
Cadillac lines up in Austin today as the first new Formula 1 team in a decade, having paid a reported 450 million dollars for the right to start from nothing. Why the price is rational, and what team, then rules, then driver predicts for them.
What Kind of Change Is This?
Specs need version numbers as much as code does, and the number should be decided by rule, not by mood. A small script that reads two versions of a document and says major, minor, or patch, with reasons.
Productized SDD vs the Real Thing
A public plugin now hard-codes most of what I do by judgment: a design gate before code, plans for a junior engineer, fresh subagents per task, test-first. Where the rigid version is right, and where lived practice diverges.
Black Monday Was an Automation Story
On October 19, 1987 the Dow fell 22.6 percent in a day, and the machines that sold were doing exactly what they were told. Thirty-nine years later, the same loop is being rebuilt out of AI agents.
The Judge Needs a Rubric
A model grading your specs is only as good as the rubric it holds and the calibration set that proves it applies it your way. The rubric, the prompt, the ten-document test, and the five ways it goes wrong.
Every Requirement Traces to Something
The first rule of spec-driven development is that nothing in the spec is inferred. Following one data gap from a question through a PRD, a mapping spec, a data contract, and into merged code, and what each artifact had to cite.
Pulling the Goalie
A 2018 paper about when hockey coaches should yank the goaltender is really about why capable people knowingly choose the worse option. I see it constantly.
The Contract Comes Before the Pipeline
A data contract is the spec's last mile: the document a consumer can hold a producer to and an agent can build from. What goes in one, why each section exists, and a template.
The Total That Was Quietly Wrong
Everyone worries a script will eat their spreadsheet chart. The chart was fine. The total formula stopped one row short, and nothing said so.
The White-Collar Apprenticeship
Germany sends about half its school leavers into paid apprenticeships, almost all of them in trades. The book I am researching argues the same track belongs in offices, and that AI makes it urgent rather than optional.
A Workspace That Maintains Itself
The difference between a tool you use and an environment you live in is who does the upkeep. Four background tasks that run without me, and the smoke test that catches a broken skill the minute it breaks.
Confidence Is Not a Reliability Signal
A model read handwritten amounts wrong and reported high confidence every single time. Asking it how sure it was gave no warning at all. Reading the same input repeatedly and checking whether the answers agreed did.
Nobody Looks in the Mirror
Everyone believes they are self-aware, and unassisted introspection mostly produces a defense brief. What actually works has artifacts, and they are not comfortable.
The Record You Can Mine
Every work session my assistant runs is logged to a store I can query. That one habit generates my standups, finds last month's fix, and shows where my own workflow has friction. A script to start with.
It Fails Plausibly, Not Loudly
An assistant read a handwritten 3/11 as 2024-03-11 with high confidence. The real year was 2026, and the invented date filed itself into a financial record without a single error.
Take What You Like and Leave the Rest
Bridgewater rewired how I work, and some of it was a machine for hurting people that thought it was a machine for truth. Both things are true. A decade-later accounting.
Go Do X and Report Back
Skills are how I do something. Agents are go do it and come back with one report. The line between them, when to dispatch, and the brief that makes a stateless worker useful.
The Migration You Can't Mandate
Deadlines and deprecation banners do not move consumers off a legacy system. Shipping the future only in the new system does.
A Human Trip
I went to Texas and did almost nothing that could be automated: barbecue in the middle of nowhere, Barton Springs before eight, a hat shop that knows my head, colleagues across a table. The tasks were all there when I got back.
Right Knowledge, Right Lifetime
An AI assistant forgets everything between sessions unless you build the memory yourself. Three scopes, one rule, and why a lesson has to land in the file that matches its lifetime.
How I Work
The six rules I actually check against when I write a spec, review an agent's output, or call something done. The long version, with the stories.
Make Something With Your Hands
The more I automate, the more the unautomatable matters. Why my most AI-powered year has also been my most physical one, and a small assignment.
Work AI vs Personal AI
The same tools on two different leashes. What running AI at a global bank and letting it run my own website taught me about each other.
Everything Is a Subscription Now
The sticker price of modern life is a fiction. The real price arrives monthly, from a dozen directions, and it is designed to never be seen in one place.
Write the Skill, Not the Answer
Solving a problem well and losing the solution is the default. A skill file turns a one-off answer into permanent capability. The structure, and the template.
The Marathon Session
Agents have no sense of time; ask one to work eight hours and it may finish in twenty. Stop estimating hours, write a real plan, and tell it to run a marathon session to the finish.
The Mandatory Vacation
Formula 1, the most competitive industry on earth, shuts down completely for two weeks every summer, by rule. Your office could learn from the rulebook.
The Gate That Fires Every Time
Telling an AI assistant how you like things works for about an hour. A rule that triggers on an observable signal works indefinitely. The pattern, and the file.
This Website Runs Itself
This site publishes a post every Sunday, sends the newsletter, and pings search engines with nobody pressing a button. A small, honest case study in spec-driven automation, told through the two nights it broke.
The Year I Got Myself Back
One year sober, and the surprise was not what I gave up but who I became. An honest note on community, reaction over circumstance, and what I would tell anyone standing on the edge.
The Spec That Lints Itself
A small, free, no-dependency script that checks a markdown spec for the gaps that force an AI coding agent to guess. Download it and run it today.
The Org Chart Lags Reality
With an agent, a lot of a role becomes automatable fast. What holds it up is rarely the technology. It is the organization: the last stretch of a job someone is unwilling to hand over, and a structure built for the old distribution of work.
Europe Is Closed
Every August my European colleagues vanish behind an out-of-office wall while American calendars barely flinch. One of these systems is being honest.
Data Products for Robots
AI agents are now first-class consumers of your data. A practical guide to what changes when the reader of your documentation is a machine.
Evaluation Is the New Code Review
In spec-driven development, writing the spec gets the attention. The skill that actually decides quality is evaluation: designing the tests that prove the output is right, which takes domain truth and failure sense at the same time.
One of My Teams Has No Engineers
I manage four product teams. Three are conventional. The fourth has no engineers: I write the specs and artificial intelligence agents build the software, with a human still reviewing every merge. A field report on what spec-driven development actually changes about the product job.
Opus 5 and the Effort Dial
Near-flagship intelligence at half the price, with a dial for how hard it thinks. The model is no longer the bottleneck. Your specs and checks are.
The Race Is the Deploy
Formula 1 heads into the summer break with half a season down. The races are the part everyone watches, but they are the deploy. The championship is decided in the development war: budget caps, wind tunnel hours, and upgrade strategy. A product person's guide to the sport's real game.
The Skills You Didn't See Coming
Spec-driven development is a real, teachable skill, and almost nobody starts with all of it. A map of the four skills it rewards, who sits where, and how any role grows into the work.
The Next Fifty Years of Entertainment
Going to the movies will become a special occasion, like going to a Broadway play. Home theater, generative content, and live experiences split the entertainment economy along new lines. Predictions for the next half century.
Why Artificial Intelligence Threatens Movies But Not Music
Theaters release about 150 wide films a year. Spotify gets tens of thousands of new songs a day. The supply structure of each industry decides which one artificial intelligence can actually disrupt and which one it can't.
We Thought Retail Was Dead
In the late 1990s, everyone agreed the internet would kill physical retail. Twenty-five years later, brick and mortar still owns 84% of sales. The story of what actually happened is the most useful lens we have for thinking about artificial intelligence right now.
I Didn't Leave the Country Until I Was Twenty-Six
The first time I crossed an ocean I was twenty-six. The lessons came in two layers. People are mostly the same. And the United States is its own continent, with the kind of internal variety most travelers cross borders to find.
Trading Isn't About Math
Everyone thinks trading is math. From 2013 to 2016 I worked in high frequency trading and futures coverage. The edge wasn't math. It was world news, poker, and psychology. And the fact that bonds still trade through chat windows tells you why.
Read Your Own Pre-Read
Letting artificial intelligence summarize the meeting, write the prep, and take the notes feels like a shortcut. The research says it's quietly making us worse at the part of the job that actually matters.
AA Is Great. It's Also Not the Only Way.
I've been sober for almost a year. AA works for a lot of people, and the data is on its side. It's also not the only way, and most of what makes it work has nothing to do with the steps.
The Tax Complexity Lobby
Americans spend 1.7 billion hours and $31 billion a year doing taxes. That's not an accident. Here are practical ways individuals can route around the lobby that wants to keep it that way.
The Best of East and West
Western medicine writes off acupuncture, tai chi, and turmeric as junk science. The peer-reviewed evidence says otherwise. The smart move is to take the best of both traditions, not pick a side.
Covid Rewrote the Dating Rules
The pandemic forced people to invert the typical dating script. Define the relationship first, meet later. The data says it actually worked better.
The Problem with the Word Smart
When we say someone is smart, we usually mean they remember things and answer questions quickly. That's one kind of intelligence. The research says there are at least seven more, and most of them matter more.
Seven Things Every Religion Figured Out
Catholic nuns and Buddhist monks independently converged on the same breathing rate. That's not theology. That's data. My book is about what it means and what you can do with it.
Is College Worth It?
Tuition has risen 13x since 1980. The average borrower takes 20 years to pay off their loans. But the earnings premium is real. The honest answer depends entirely on what and where you study.
The Long Road to Representative Leadership
Fortune 500 CEOs are 89% male and overwhelmingly white. At the current rate, demographic parity is decades away. Some of the headlines celebrating progress are actually part of the problem.
The Best Way to Write a Date (And Why Almost Nobody Does It)
There are three ways to write a date. Most of the world picked one, the US picked another, and the objectively correct answer is the one almost nobody uses in conversation.
The Junior Role Is Disappearing. What Happens in 25 Years?
Entry-level jobs are vanishing faster than anyone expected. If artificial intelligence replaces the first rung of the career ladder, where will tomorrow's leaders come from?
The Tipping Problem Nobody Wants to Solve
Restaurants have tried eliminating tips. Servers hated it. But the alternative is a system where 20% of Americans still tip for terrible service. Something has to give.
Nuclear Energy Has a Marketing Problem, Not a Safety Problem
Nuclear power causes 99.9% fewer deaths than coal per unit of energy. The Chernobyl death toll was a fraction of what most people believe. So why are we still afraid?
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