alt Hacker NewsYeah, this one is bad because it’s off by so much I’m shocked it wasn’t caught by tests, alerts about unusual changes in the billing system, or even accounting. Like surely the P&L reports look all kinds of wrong right now, they have to be showing like 6M% profit margins and revenue measured in quadrillions.
I’m also a little surprised this didn’t trip a circuit breaker. For something as non-real-time as billing, I’m surprised they don’t have an automated kill switch that pauses the billing system and fires a page if variance in bills spikes. Naively some kind of “if the standard deviation of customer bills for this year changes by more than 50%, pause the billing system”. At that number of customers, those numbers should be pretty stable beyond internal billing changes they could normalize for.
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I don’t know how something like this makes it to prod. That’s multiple levels of failure.
If I were to guess this bug is in the "display" part of the system which is probably distinct from the "actually take money from the customer" part of the system. One can imagine they have gates on the "actually take money" part, especially for a large bill like ours which was ~$300b or about 2.5x AWS' 2025 revenue... In one month. Surely if we had actually accumulated that bill they would be the ones with the problems when we can't pay it.