At best it’s checking available credit. All the other stuff is done after the fa... | Hacker News

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		mattclarkdotnet 37 days ago \| parent \| context \| favorite \| on: Migrating the American express payment network, tw... At best it’s checking available credit. All the other stuff is done after the fact. The idea that any banking transaction involves “subtracting one number from another” is so wrong it’s barely worth engaging with.

dcrazy 37 days ago | [–]

You speak so confidently, yet it appears you’ve never gotten a text asking you to approve or deny a charge that you are performing.

skywhopper 37 days ago | [–]

Some (rewards processing) is probably done later, but the fraud check definitely isn’t.

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