x402go

x402Go — Pay-as-you-go x402 payments for APIs on Celo

The problem. Developers using a prepaid x402 facilitator must fund a balance before accepting payments. This adds friction, requires upfront capital, and leaves developers managing credits and top-ups.

The solution. x402Go is a pay-as-you-go x402 facilitator for developers selling APIs on Celo. Developers sign in with their wallet, get an API key, and configure x402Go as the facilitator for their resource server. They can start accepting payments without pre-funding a facilitator account.

How it works. x402Go verifies payment authorizations and settles them on-chain. In a single atomic transaction, the payer's authorization is executed and the payment is split: the merchant's net proceeds go to their configured payout wallet, while the fee goes to the protocol's fee collector. x402Go supports EIP-3009 and Permit2 SignatureTransfer, depending on the token.

Merchant proceeds are delivered directly to the merchant's payout wallet during settlement. There is no merchant balance held on the platform and no separate withdrawal process.

Security. Each merchant has a deterministic vault. The operator cannot arbitrarily choose the merchant's payout destination; changing the payout address requires authorization from the merchant.

Supported assets. USA₮, cNGN, USDC and USD₮ on Celo Mainnet.

Built with. TypeScript, Bun, Express, viem, MongoDB, Solidity, Foundry, Solady, React and wagmi.