If your customers pay in their own currency and you pay affiliates in yours, every payment carries two different amounts. Pick the wrong one and every commission you calculate is quietly wrong.
Two amounts, two currencies
Stripe calls the currency the customer is charged in the presentment currency, and the currency that lands in your account the settlement currency. When they differ, Stripe converts, and the conversion is where commission math goes wrong.
The invoice tells you what the customer paid. The balance transaction tells you what you actually received.
// invoice.paid
