Glossary
terms of art · with coinage and date
The field mints vocabulary faster than it mints evidence. Each entry names its source and date, so you can tell a five-decade-old term from one coined last quarter.
Agent factory
microsoft (yina arenas, azure blog series) · from 2025-08-13Microsoft’s parallel coinage: a repeatable blueprint for enterprise agentic AI, productized at Ignite 2025 as Microsoft Agent Factory. Same instinct, different layer — governance and platform rather than the code pipeline.
Back pressure
horthy (humanlayer); also huntley as “back pressure engineering” · 2025–2026The governing constraint of factory design: hand a loop only as much autonomy as you can cheaply and reliably verify. Borrowed from fluid dynamics via streaming systems, where a slow consumer must throttle a fast producer. Chapter 3.
Comprehension debt
osmani, essay series through “software factories, light and dark” · 2025–2026The widening gap between how much code exists and how much any human still understands. A dark factory accumulates it at full speed while every test stays green. Sibling of Thoughtworks’ “cognitive debt.” Chapter 2.
Dark factory
shapiro, “the five levels” · 2026-01-23A software pipeline that ships code no human has read, verified only by machines. Named for FANUC’s lights-out plants — dark because robots don’t need to see. Shapiro’s level 5; StrongDM’s Software Factory is the reference implementation. Chapters 2 and 5.
Digital Twin Universe (DTU)
strongdm · 2026-02Behavioral clones of external dependencies (Okta, Jira, Slack, Google Docs) built by agents from public API docs, so scenario tests can run thousands of times per hour without rate limits. One of the three inventions that make the reference dark factory possible. Chapter 5.
Harness engineering
böckeler (thoughtworks), martinfowler.com · 2026-04-02Designing the walls around the loop: guides that steer an agent before it acts, sensors that observe it after, and the human’s steering loop iterating on both. Formula, credited by her to LangChain: agent = model + harness. Chapter 1.
Light factory / lit factory
osmani; re:cinq’s “lights-on” · 2026The same pipeline as a dark factory with the lights left on where judgment lives: agents build, humans approve — and judgment moves upstream to plans and architecture. The dominant production reality of mid-2026 (Stripe, Spotify, Cursor). Chapters 2 and 4.
Loop engineering
osmani (related essay series) · 2025–2026Designing the small system that prompts the agent instead of prompting it yourself: context in, action, check, repeat, with a defined exit. The smallest unit of factory craft. Chapter 1.
Ralph loop
huntley · 2025-07A coding agent in an infinite shell loop, re-reading the same prompt file each iteration, using the filesystem and git history as memory and starting every cycle with a fresh context window. Named for Ralph Wiggum, “deterministically bad in an undeterministic world”: the dumb persistence is the feature. “Sit on the loop, not in it.”
Satisfaction
strongdm · 2026-02A probabilistic success metric replacing boolean “tests pass”: what fraction of observed trajectories likely satisfy the user. How a dark factory grades work when no human will look. Chapter 5.
Software factory
mcilroy 1968; sdc trademark 1974; ai-era repurposing 2025–2026A term five decades older than the hype: McIlroy’s reusable-components vision, trademarked by Systems Development Corporation in 1974. Now repurposed to mean an agentic pipeline turning specifications into working software — many harnessed loops, a queue in, a review gate out. Chapter 1.
Spec-driven development (SDD)
github spec kit, bmad, openspec, kiro · category exploded 2025Specifications as the executable source of truth — constitution files, plan templates, acceptance criteria — replacing “vibe coding.” The on-ramp through which most teams reach factory patterns. Chapter 5.
Verification debt
vogels (aws) · 2025–2026The accumulating cost of AI-generated code that was merged but never truly verified. The financial metaphor is exact: the balance compounds quietly and comes due at the worst time. Chapter 3.