Compass moves freight bookings across Europe. Sixty-odd services, twelve teams, and — before this window — three separate products in the paging path, each with its own idea of what an incident was.
Their problem was not sensitivity. It was arithmetic. When the routing service degraded, every service downstream of it reported its own symptom, and each symptom had its own rule. One failure produced forty-one notifications across three tools, and the on-call engineer's first job was always to work out whether they were looking at one problem or forty.
We were not short of information. We were short of a system that could tell us the information was all about the same thing.
M. OKAFOR · PLATFORM LEAD · COMPASS
One failure, one incident
Because Compass's telemetry carries a shared identity from the edge, a burn that propagates through the dependency graph resolves to a single incident with the implicated services ranked by when they started degrading. The routing service appears at the top because it degraded first, not because someone guessed it would.
That change alone accounted for most of Compass's reduction. Their alert volume fell from three hundred and ten a week to four, and roughly two-thirds of the drop is deduplication rather than anything to do with severity or budgets.
Consolidating the paging path
The second change was administrative. Compass had metrics in one product, logs in another, and traces in a third, which meant an incident review involved three exports and a spreadsheet. Consolidating removed a class of work that nobody had ever counted as work.
- Twelve teams moved onto shared objectives rather than per-team thresholds.
- Three invoices became one, with no per-host or per-metric line.
- Incident reviews stopped requiring a data export.
The rotation
Okafor's stated measure of success was not volume. It was whether engineers were declining to travel during their on-call week. In the quarter before the migration, four people had. In the quarter after, none did.
At the end of the window Compass moved their remaining two teams over without asking us for anything. Okafor's summary was that the rotation had become an ordinary week, which is the only outcome we have ever claimed to be selling.