# Ed4l02 — XRPL x402 Payment Infrastructure

> Ed4l02 is an open-source payment infrastructure built on the XRP Ledger (XRPL).
> It implements the x402 protocol: any HTTP API endpoint can be monetised with a single line of middleware.
> Payments settle on-chain in seconds. No bank, no OAuth, no subscription required.
> Designed for AI agents, autonomous systems, and human users alike.

## What is Ed4l02?

Ed4l02 is a full-stack payment layer for the machine economy:

- **x402 middleware** (`@hliosone/ed4l02-x402`): Express.js middleware that payment-gates any API route. One line of code.
- **Facilitator**: A settlement server that verifies XRPL transactions and releases access to protected resources.
- **Merchant portal**: Revenue dashboard, transaction history, ISO 20022 / CAMT.053 export, XRP↔RLUSD swap.
- **Marketplace**: A public registry of pay-per-use API endpoints, browsable by AI agents and humans.
- **Identity layer**: On-chain KYC credentials (XLS-70) issued via Edel-ID, verified without third-party calls.
- **VAT-aware payments**: Automatic HT/TVA/TTC breakdown for FR (20%) and CH (8.1%) jurisdictions, stored on-chain.

## How it works

1. A client (human or AI agent) calls a protected API endpoint.
2. The server responds `HTTP 402 Payment Required` with payment details (destination wallet, amount in drops, network).
3. The client signs an XRPL Payment transaction and replays the request with the signed blob as a header.
4. The facilitator verifies the transaction on-chain and settles. The resource is released.

This is the x402 protocol — permissionless, cryptographically verifiable, instant finality.

## npm package

```
npm install @hliosone/ed4l02-x402
```

### Usage (one line)

```js
import { xrpl402Express } from "@hliosone/ed4l02-x402";

app.get("/api/data", xrpl402Express({
  facilitatorUrl: "https://facilitator.edel-id.ch",
  network: "mainnet",
  asset: "XRP",
  amount: "1000000",   // 1 XRP in drops
  payTo: "r...",       // merchant XRPL address
}), handler);
```

## Live endpoints

- Facilitator API: https://facilitator.edel-id.ch
- Marketplace: https://ed4l02.vercel.app/marketplace
- Merchant portal: https://ed4l02.vercel.app/merchant
- User / identity: https://ed4l02.vercel.app/user

## Source code

- Package: https://github.com/hliosone/ed4l02-x402
- Platform: https://github.com/hliosone/ed4l02

## Key concepts for AI agents

- **Payment address**: an XRPL classic address (starts with `r`)
- **Amount**: expressed in drops (1 XRP = 1,000,000 drops)
- **Network**: `testnet` or `mainnet`
- **Credential types**: `EDEL_KYC_OVER_18`, `EDEL_TVA_FR`, `EDEL_TVA_CH` (XLS-70 on-chain credentials)
- **Settlement**: final when transaction appears in a validated ledger (`tesSUCCESS`)
- **No wallet needed server-side**: the facilitator only verifies, never holds funds

## For AI agents: how to pay an x402 endpoint

1. `GET /endpoint` → receive `402` with `X-Payment-Required` header (JSON with `accepts` array)
2. Parse `accepts[0]`: extract `network`, `amount` (drops), `pay_to` (destination address)
3. Sign an XRPL `Payment` transaction: `Account=your_address`, `Destination=pay_to`, `Amount=amount`
4. Encode as `PaymentPayload`: `{ scheme: "xrpl-v1", network, tx_blob, from_address }`
5. Base64-encode the JSON and set header `X-Payment-Signature: <encoded>`
6. Replay the original request with that header → receive `200` with resource

## Contact / team

Built at Paris Blockchain Week 2026 hackathon.
Repository: https://github.com/hliosone/ed4l02