Stableflow: Self-Hostable Stablecoin Payment Rails for Indie SaaS
A drop-in Next.js middleware that lets any SaaS accept USDC on Base/Polygon/Arbitrum with subscriptions, webhooks, and a hosted checkout — no Stripe required.
Indie SaaS founders want to accept stablecoins (USDC/EURC) to reach crypto-native customers and avoid Stripe's 2.9% + risk of sudden account freezes, but cobbling together wagmi checkout, nonce management, subscription state, and refund flows takes weeks per chain.
Solo SaaS founders and indie hackers selling to crypto-native customers who want USDC/EURC billing without building payment infra.
npm package with Next.js middleware: createCheckoutSession(amount, interval), verifyPayment(headers), webhook handler. Hosted checkout page at pay.stableflow.dev. Dashboard for MRR, churn, refunds. Support USDC on Base, Polygon, Arbitrum at v0.
I've built wagmi + viem payment flows in production; combining that with Stripe-style subscription UX (proration, dunning, refund) is exactly where my skill set compounds.
Requires deep knowledge of EIP-3009 transferWithAuthorization (gasless USDC), EIP-2612 permit signatures, ERC-20 approve race conditions, Base/Polygon/Arbitrum block times and finality differences, x402-style payment-protocol patterns, and the operational edge cases of refunds (you can't 'reverse' an ERC-20 transfer — you need a custodial outflow).