@erudite-intelligence/x402-apt

x402 exact payment scheme implementation for Aptos APT.

Part of the EruditePay x402 multi-chain payment infrastructure by Erudite Intelligence LLC.

Overview

This package implements the x402 protocol's exact payment scheme for the Aptos blockchain. It enables HTTP 402-based micropayments using native APT coin transfers via aptos_account::transfer_coins.

• CAIP-2 Network ID: aptos:1
• Unit: octas (1 APT = 100,000,000 octas)
• Signing: Ed25519 via @aptos-labs/ts-sdk
• Verification: Aptos fullnode REST API

Installation

npm install @erudite-intelligence/x402-apt

Usage

Client — Create a Payment

import { createPayment } from "@erudite-intelligence/x402-apt";

const paymentHeader = await createPayment({
  senderPrivateKeyHex: "abcdef1234...",
  recipientAddress: "0xabc...",
  amountOctas: "100000000",  // 1 APT
  network: "mainnet",
});

Server — Verify & Settle

import { verifyAndSettle } from "@erudite-intelligence/x402-apt";

const result = await verifyAndSettle({
  paymentHeader: req.headers["x-payment"],
  expectedRecipient: "0xabc...",
  expectedAmountOctas: "100000000",
  network: "mainnet",
});

if (result.success) {
  console.log("Settled:", result.txHash);
}

Security

• Replay protection: In-memory Map with 1-hour TTL. Multi-instance deployments MUST use Redis/DB.
• Fail-closed: If balance query or fullnode API fails, the payment is REJECTED.
• Expiry enforcement: Transaction expiration timestamps are checked before submission.

License

MIT — Erudite Intelligence LLC