Crypto Checkout Flow

This document describes the lifecycle and user flow of the Rach Finance Crypto Payment Gateway.

1. Merchant Creates Checkout

The merchant's server calls the POST /checkout/create endpoint with the order details (amount, currency, reference).

• The system generates a unique Deposit Address (for crypto) or provides bank details (for fiat).
• A session_id is returned.

2. User Makes Payment

The user is presented with the payment instructions (QR Code + Address).

• The user sends the exact cryptocurrency amount to the generated address.
• Supported Networks: BSC, ETH, Polygon, Tron, Solana.

3. Monitoring & Detection

Rach Finance's Payment Monitor Service continuously watches the blockchain for incoming transactions to the generated address.

• Detection: Once a transaction is seen in the mempool or block.
• Confirmation: The system waits for the required number of block confirmations (e.g., 12 for BSC, 3 for BTC).

4. Payment Confirmation

Once confirmed:

• The Checkout Session status changes from pending -> paid.
• The merchant's ledger balance is credited immediately (net of fees).
• An email receipt is sent to the customer.
• An email notification is sent to the merchant.

5. Webhook Notification

If a callback_url was provided, the system sends a webhook POST request to the merchant's server.

{
  "event": "payment.confirmed",
  "data": { "reference": "...", "status": "paid", "tx_hash": "..." }
}

6. Settlement

The funds collected are swept from the temporary deposit address to the merchant's main Hot Wallet or Treasury Wallet periodically by the Sweep Service.