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Shipped2026

CityPulse

Per-API nanopayment monetization for municipal traffic

Live siteRepository

Stack

  • Next.js
  • Solidity
  • Arc
  • Circle Nanopayments
  • MapLibre

Highlights

  • ·Circle × Arc Nanopayments hackathon entry
  • ·Route and Parking contracts, 36k+ transactions
  • ·3D MapLibre navigation, 80-vehicle Istanbul simulation
  • ·Circle Gateway, Wallets, and Bridge Kit integration

Problem

Municipal traffic APIs are valuable but priced for enterprise. A developer running a single trip-planning prototype has no way to pay $0.0001 for one route call because the billing rails do not exist below a cent.

Approach

Each API call carries an x402-style receipt settled through Circle's Nanopayments primitive. Two contracts, Route and Parking, sit behind the gateway. Circle Wallets and Bridge Kit handle balance plumbing. A 3D MapLibre frontend with an 80-vehicle Istanbul simulation demonstrates the flow at realistic load.

Outcome

V2 live at citypulse-v2.vercel.app. Route contract has processed 36,000+ transactions. Submission-ready for the Per-API Monetization Engine track.