It Works on My Machine
A release only ever builds green on one developer's machine, and nobody knows which of its thousand undocumented settings is load-bearing. Echo wants to reproduce it clean. Root asks what happens the day that laptop is left on a train.
When the build lives on one man's laptop, the laptop is the company.
The release had shipped for three years, and for three years it had only ever built on Dmitri's laptop.
Echo found this out the way you find out a wall is load-bearing: by asking an innocent question. "Where's the build server?" "There isn't one. Dmitri runs it. On his machine. Friday afternoons."
She'd asked Dmitri to write down how. He'd tried — four pages that ended, honestly, with "and then it works, I don't know why." An env var set in 2019. A patched library he couldn't remember patching. A folder that had to exist, written by nothing anyone could name.
"It's a cauldron with one leg," Root said.
"It's a single point of failure. I want it in CI — reproduced clean, in a container, so anyone can build it."
"Good. Do that." He didn't often just agree. "And while you do, picture the leg breaking. Not the laptop dying in a year — today. He spills coffee in it at lunch. The meal's on the floor, the prince is soiled, four hundred customers don't get Friday's release, and the one man who knew which thousand settings mattered is at the Apple Store filling out a form."
"That's why I'm containerizing it."
"I know. I'm telling you why it's the most important thing you'll do this quarter and the least visible. Nobody throws a party for the build that already worked. You'll spend three weeks proving the leg, and the only sign you succeeded is that a day you were dreading never comes."
"Dmitri won't like it. The Friday build is sort of his."
"It's his because no one made it the company's. That's not loyalty, it's a hostage situation everyone's being polite about." Root stood. "Reproduce it. Every setting, in the open, where the meal cooks in a pot anyone can carry. A vessel the whole kitchen can lift isn't less special than a magic one. It's just the one that survives the cook getting the flu."
"Works on my machine" is funny until the machine is the only one it works on. When a build, deploy, or critical job lives in one person's undocumented local environment, that person — and their hardware — silently becomes a single point of failure for the whole organization. The fix (reproducible builds, CI, containers, infrastructure-as-code) is unglamorous, and its success is invisible: a disaster that simply never happens.
Inspired by Snowflake Server (Martin Fowler).
The legs of the ting are broken. The prince's meal is spilled and his person is soiled. Misfortune. A difficult and responsible task to which you are not adequate. Moreover, you don't devote yourself to it with all your strength but go about with inferior people. Therefore the execution of work fails. Confucius says: 'Weak character coupled with honored place, meager knowledge with large plans, limited powers with heavy responsibility—this will seldom escape disaster.'
The figure. ䷱ The Cauldron (Dǐng), line 4 changing → ䷑ Work on What Has Been Spoiled (Gǔ). "The legs of the ting are broken. The prince's meal is spilled and his person is soiled. Misfortune." A vessel that feeds everyone, balanced on one leg — limited powers under heavy responsibility. Confucius on this line: "meager knowledge with large plans, limited powers with heavy responsibility — this will seldom escape disaster."
The reading. A cauldron the whole kitchen can lift isn't less special than a magic one — it's the one that survives the cook getting the flu. Reproduce the build in the open before the leg breaks, not after.
Department: Engineering (工)