About

method · sources · provenance

AI Factories is a tutorial on software factories in the AI era, frozen conceptually at July 2026 and extended forward through its updates log. It is written for two readers: the senior developer who suspects “dark factory” is marketing, and the engineering manager deciding whether and how to invest. The editorial contract for both: every volatile claim is dated and carries its class (measured, vendor-reported, or our experience), and the places where the evidence is genuinely unsettled say so.

Sources

The conceptual frame of chapters 1–4 paraphrases and builds on:

• Addy Osmani, Software Factories, Light and Dark (Substack, 2026-07-22): the light/dark frame, comprehension debt, the closed-loop diagram, and the “where the human goes” argument. Related posts by the same author on loop engineering and owning the outer loop.
• Dex Horthy (HumanLayer), Harness Engineering is not Enough: Why Software Factories Fail (AI Engineer World’s Fair, 2026) and 12-Factor Agents: the factory wiring, the four-month dark-factory report, the 3–10-step rule, back pressure.
• Dan Shapiro, The Five Levels: from Spicy Autocomplete to the Dark Factory (danshapiro.com, 2026-01-23): the levels model and the term “dark factory” as applied to software.
• Birgitta Böckeler (Thoughtworks), harness engineering (martinfowler.com, 2026-04-02): guides, sensors, and the steering loop.

The mid-2026 snapshot (chapter 5) additionally draws on the Stripe Minions engineering posts (2026-02), Spotify’s Honk presentation at QCon London via InfoQ (2026-03), Cursor’s agent posts (2026-02/04), StrongDM’s Software Factories and the Agentic Moment (2026-02), Geoffrey Huntley on Ralph loops (2025-07), the Sonar State of Code survey (2026-01-08), the METR randomized trial (arXiv 2507.09089) and METR’s subsequent walk-back (2026-02), Simon Willison’s commentary, and funding/valuation reporting on Cognition and Factory.ai (2026-04/05). Chapter 6 is original: its evidence is the run journals, design notes, and retro reports of this workspace’s four factories, including the website-factory darkening analysis of 2026-07-24.

Update policy

The chapters change only when the theory does. The snapshot is corrected, never silently rewritten; corrections and new developments are dated entries in the updates log. Corrections are welcome and wanted: an error report is a signal, and this factory turns signals into queue items, which is the mechanism chapter 3 describes.

Colophon

Design system: Switchboard. Light mode is the lit factory, dark mode the lights-out floor; lamp amber marks human judgment, machine blue marks automated verification. Type: Big Shoulders Display, Newsreader, JetBrains Mono. Built with Jekyll on GitHub Pages; diagrams are inline SVG keyed to the palette tokens, so they re-light when you flip the switch.