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Writing

Notes from the workshop.

Essays on building bespoke software, the Elixir ecosystem, and why most companies need fewer engineers than they think.

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Featured

Domain Authority in 2026 Is Still Earned the Old Way

Winnow Labs went from a Domain Rating of 2 to 8 in six months without tricks. It published research that people and AI agents both want to read.

David Kerr
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Every One of Them Scored 42. None of Them Are Real.

I opened my backlinks report and found a wall of .store domains, all with the same Domain Rating. They are one spam operation, not real businesses.

David Kerr
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Astra Can Use a Computer. That Was Never the Hard Part.

GPT-6 Astra reads a screen and drives the mouse. Priced today, one clerical workflow costs about what a person costs. The supervision layer is missing.

David Kerr
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What a Token Turned Out to Be Worth

I ran the same task 419 times over weeks to find out whether a token's value moves. It does not. The model is the only lever I could measure.

David Kerr
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116,000 Papers on Leftover Tokens

The Winnow Research Atlas holds 116,439 papers. Its pipeline runs by hand off my laptop. What that taught me about deterministic filters and materialized views.

David Kerr
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The Frontier Comes to You

You will never catch the AI frontier, and you do not have to. Model efficiency doubles every eight months, so last year's frontier lands on your desk.

David Kerr
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What Is a Token Worth?

Tokens are the raw material of my work, but a subscription never tells me what one is worth. So I am instrumenting my own plan for weeks to find out.

David Kerr
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Who the Data Centers Are For

In three weeks of June, the most capable AI model went to institutions, the public got a smaller window, and the bill keeps landing on the rest of us.

David Kerr
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Renting the Frontier

What does it cost to run your own AI coding model? I did the math. Cost is not the problem. The real risk is depending on a few vendors you can't control.

David Kerr
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Stop Burning Tokens. Start Allocating Them.

The cheap-token era is ending, but the limit that stops you is the window, not the price. Here's how to treat AI capacity like a budget you allocate.

David Kerr
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I Built a Video Game. The Domain Wasn't the Constraint.

Domain expertise used to be the moat. It isn't anymore. The three skills that replaced it, tested against a domain I had never worked in.

David Kerr
A workshop bench with two sets of plans pinned to the wall, one zoomed out and one zoomed in
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How to Tell If You're Using AI Well

Volume metrics lie about AI-assisted work. The signal isn't in the code, it's in whether you did the thinking before the code got written.

David Kerr
A conductor's podium with tools and blueprints scattered around it
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You're the Broker, Not the Builder

AI coding assistants are good enough to do the building. Your job is brokering between the problem and a solution that scales and survives contact.

David Kerr
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The Age of Bespoke Software

Software used to be something only tech companies could justify building. That is not true anymore, and most businesses have not worked out what changes.

David Kerr
A workbench with tools and a half-finished project
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Builders Build for Fun. That's How You Get Hired.

Building Winnow Labs a blog and a research atlas for fun turned into a real partnership. Between jobs, the best thing you can do is build something.

David Kerr
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Amazon Buys Rivr. I've Seen This Before

I built robots at a company Amazon bought. The Rivr acquisition runs into the same cost and scale problems that killed the last delivery robot.

David Kerr
PostgreSQL elephant and GraphQL logo side by side
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You Probably Don't Need GraphQL (Yet)

Most Phoenix apps don't need GraphQL. Here's how to know when PostgreSQL and Ecto are enough, and when Absinthe actually earns its complexity.

David Kerr
Abstract visualization of Elixir processes communicating like AI agents
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Elixir Was Built for Agentic AI (40 Years Early)

Erlang was designed for isolated processes with their own state, communicating over unreliable networks. That's exactly what agentic AI looks like.

David Kerr
Two developers collaborating as engineering partners
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Build Allies, Not Headcount

Engineering is a partnership, not a transaction. The companies that move fastest are the ones whose engineers actually understand the business.

David Kerr
Elixir and Phoenix logos over abstract code patterns
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Why I Build Everything in Elixir and Phoenix

From MVP to millions of users, Elixir and Phoenix handle it all. In the age of AI, that flexibility matters more than ever.

David Kerr
Developer working with AI coding tools at a desk
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I Was Wrong About AI

For a year I said AI coding tools only added 20% efficiency. I was measuring the wrong thing. What changed, and how I work with them now.

David Kerr
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Why I Started Kerrberry Systems

After 8 years building software at Amazon Robotics and GridPoint, I went out on my own to build for small teams stuck between big vendors and busy IT.

David Kerr

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