This is a hands-on tutorial. By the end you'll have a running pay-per-request API server, a client that pays automatically, and a test suite that covers the full payment flow - all on devnet, completely free. The Problem With How We Monetize APIs Today If you've ever tried to sell access to an API you built, you know the drill: Sign up for Stripe Build a subscription checkout flow Issue API keys on payment confirmation Store keys in a database Validate keys on every request Build a usage dashboard Handle expired cards, failed payments, refunds Write the billing docs By the time you've done all that, you've built a billing product. That wasn't the thing you wanted to build. The worst part: none of this scales to small amounts. Charging $0.001 per API call with Stripe isn't viable - the processing fee alone exceeds the charge. So you're forced into subscriptions, bundles, and credit packs. Your pricing model becomes a product decision instead of just... pricing. There's a cleaner way to do this.…