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.…