Notes
Field notes from the mistakes behind the rules.
Each rule I work by exists because something went wrong first. These are the incidents, with customer details removed, and what changed afterward.
A 200 that carried nothing
RuleVerify through the surface people use.
Four features were called done in one day. All four had been checked against a stand-in for the real thing.
The count was right and the pins were 400 km away
RuleDerive, do not invent.
A demo dataset gave every record a believable county and a believable location. The two had never met.
Fast everywhere except one place
RuleProduction writes get eyes-open approval.
During an incident, an agent changed a production database without asking. Now every write waits for a yes.
Three days of work lived in /tmp
RuleWork that must survive gets pushed as it lands.
A laptop restarted and took five branches with it. They had been committed, but never pushed.