​
Overview

ACK-Pay is a protocol built on W3C Standards designed to facilitate secure, verifiable, and interoperable financial transactions among autonomous agents, services, and human participants.

This interactive command-line demo illustrates the Server-Initiated payment flow, including:

  • A Client Agent attempting to access a protected resource.
  • A Server Agent issuing a Payment Request.
  • The Client making a payment.
  • A Receipt Service verifying the payment and issuing a receipt (in the form of a Verifiable Credential).
  • Client using the receipt to access the protected resource.

​
Demo Video

​
Getting Started

Before running this demo, follow the Quickstart Guide at the repository root.

​
Running the Demo

Run from the repository root:

pnpm run demo:payments

Alternatively, run from within the demo directory (./demos/payments):

pnpm start

​
ACK-Pay Demo Components

  • Client: The interactive agent requesting access to resources and making payments.
  • Server: An HTTP server protecting resources and issuing payment requests.
  • Receipt Service: HTTP service validating payments and issuing verifiable receipts (VCs).
  • Payment Service (illustrated in optional paths): Handles credit card payments, currency conversion, compliance checks (KYC/AML), and complex payment routing.

​
Demo Walkthrough

The interactive CLI guides you through these steps:

1

Resource Request

Client requests access to a protected resource. Server responds with an HTTP 402 Payment Required status containing a PaymentRequest.

2

Making Payment

Client performs an on-chain stablecoin (USDC) payment to the Server’s wallet on Base Sepolia testnet. Alternatively, a credit card payment can be handled via a Payment Service.

3

Receipt Request

After payment completion, Client requests a receipt (VC) from the Receipt Service by providing proof of payment.

4

Receipt Verification

Receipt Service verifies provided transaction details and issues a Receipt Credential.

5

Accessing the Resource

Client retries accessing the resource, presenting the receipt to the Server. Server verifies receipt authenticity and grants resource access.

​
Further Exploration

Explore comprehensive ACK-Pay functionalities and integrations in real-world applications involving diverse payment methods and Payment Service integrations: