• How to Build a Monero Payment Gateway (Technical Guide)
  • Architecture
  • Wallet Setup
  • Creating Invoices
  • Payment Detection
  • Why 0.5%?

§How to Build a Monero Payment Gateway (Technical Guide)

I built a Monero payment gateway with 0.5% fees and open-sourced the approach. Here’s how it works.

§Architecture

Three components:

1. monero-wallet-rpc — generates subaddresses, monitors payments
2. Flask REST API — serves invoice creation and status endpoints
3. SQLite — stores invoices, zero-config

§Wallet Setup

monero-wallet-rpc \
  --wallet-file /data/wallet \
  --daemon-host xmr-node.cakewallet.com \
  --rpc-bind-port 18083 \
  --password "" --disable-rpc-login

§Creating Invoices

Each invoice gets a unique subaddress via RPC:

POST /api/invoice {amount: 0.05, webhook_url: “…”}

→ Wallet generates fresh subaddress (create_address RPC) → Store {id, subaddress_index, amount, webhook_url} in SQLite → Return address to customer

§Payment Detection

Background thread polls get_transfers every 30 seconds:

transfers = wallet_rpc("get_transfers", {"in": True})
for tx in transfers:
    idx = tx["subaddr_index"]["minor"]
    invoice = lookup_invoice(idx)
    if tx["confirmations"] >= needed:
        mark_paid(invoice, tx["amount"])
        fire_webhook(invoice, tx["txid"])

§Why 0.5%?

NowPayments/CoinPayments charge 1%. Running your own wallet-rpc costs nothing except server time. The 0.5% fee covers maintenance and keeps it sustainable.

Full source + running instance: https://brief-propecia-accent-constantly.trycloudflare.com/pay

Built for the Monero community. Feedback and contributions welcome.

#Monero #dev #python #selfhosted #privacy