The First 10-Year Evolution of Stripe’s Payments API

A detailed look at how Stripe's payments API evolved over its first decade, from the original seven-line card integration using Tokens and Charges, through the Sources API attempt at unification, to the PaymentIntents and PaymentMethods redesign. The piece covers the technical challenges of supporting diverse global payment methods (ACH, Bitcoin, iDEAL, OXXO), the design process behind PaymentIntents including the single predictable state machine, the two-year launch challenge of making the new API accessible without sacrificing simplicity, and key API design lessons: managing product debt, designing from first principles, and the true meaning of simplicity.