VCN #37: Settlement — Build an x402 Paywall

​One agent pays another. On chain. Thirty seconds. x402 plus ERC-8004.

​x402 is a Coinbase-incubated open protocol reviving HTTP 402. It runs on Base, Polygon, Arbitrum, World, Solana. EIP-3009 tokens (USDC, EURC) or Permit2. Free tier 1,000 tx/month, then $0.001/tx. Base settlement is ~200ms. Stripe started using it in February. AWS Bedrock AgentCore Payments shipped on it in May. The Bazaar (the agent marketplace built on x402) has 10,000+ paid endpoints. Hundreds of millions of transactions since May 2025.

​And almost nobody at a meetup has wired the seller side from scratch.

​VCN #37: Settlement is the night we do.

​Format:

1. ​The thirty-line paywall. Express middleware: GET /weather returns 402 without payment, 200 with an X-PAYMENT header. Live.

2. ​Pay from a testnet wallet. Base Sepolia faucet gives free USDC. The round-trip is a single HTTP call.

3. ​ERC-8004 identity. Three registries — Identity, Reputation, Validation. The cryptographic answer to "who is calling my paywall, and is their wallet a robot you can trust." x402 is the money; ERC-8004 is the trust. They are intentionally orthogonal.

4. ​The 30-second autonomous loop. One agent discovers an endpoint, pays, gets the response. No human in the loop.

​By 10pm your endpoint earns USDC from an agent. Real money — well, testnet USDC, but the bytes are real.

​Builders only. Some crypto fluency helps but the demo flow doesn't require it.

​Doors 7pm. Talks 7:30. Frontier Tower Floor 9.

​Hosted by Vibe Coding Nights: Rayyan Zahid (Immersive Commons), Michalis Vasileiadis (Otto / GSD2.0), Eric Mockler (logistics, F11 Health & Longevity), Devinder Sodhi (Tower Lead, Frontier Tower).

​RSVP if you want to bill an agent.