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Comment by kdeldycke | Hacker News Reader

Small bills are cool, until it's too small.

I remember having to negotiate with Stripe the removal of their lowest limits. The quantum of unit I was billing on my cloud platform was such that you could consume just enough CPU and storage to end up with a $0.01 invoice at the end of the month.

It was impossible for Stripe to process this payment. IIRC their lowest limit was $0.50 or $0.10. I guess they had this limit in place to prevent abuse and limit fraud. As we had similar hard-coded heuristics for the same reasons.

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Small bills are funny. I'm surprised if the interchange fees don't net out negative for the biller.

My most recent Rackspace bill was $0.05. I don't even remember what I'm using it for any more, but it's not worth it to check out.

My last Pulumi bill was $0.86.

> surprised if the interchange fees don't net out negative for the biller

That's worth investigating!

Now in a fictional, adversarial way, you can think of a bot exploiting this discrepancy to bankrupt a competitor: create dozens of fake accounts, consume just shy of $0.01 of resources, and have the platform pays 30x more in payment fees (public Stripe price is 30¢/transaction).

To incur a net loss of $1,000,000, you’ll have to find an antagonist ready to create 3,448,276 accounts (1_000_000 / (0.30 - 0.01)), each with their own identity and mean of payment, for a total of $34,482.76.

Fortunately this is highly impractical and will be caught real fast by your internal anti-abuse systems (you have those in place right?).

Is it that impratical?

Small players would be impacted by a 100k$ net loss...and you could even spread it out over several months to be less likely to be caught by anti-abuse systems...

I was in this position and Stripe let me carry over the line items until eventually an invoice was billable, if I recall correctly. Though I might have just manually waived these charges as a courtesy.

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