Self-Hosted UPI Payment Gateway

Own-account UPI collection gateway with automatic payment matching — no third-party fees.

2026-07 — present

Node.jsExpressSQLiteAndroidnginxPM2Webhooks

Key Features

◆ Unique-paise payment matching
◆ Real-time confirmation via notification reader
◆ Merchant API + webhooks
◆ Admin dashboard
◆ Zero gateway fees

The problem

Indian payment gateways charge 2%+ per transaction and hold settlements. For high-volume, low-ticket businesses that's a real cost.

What I built

A complete self-hosted UPI collection system:

Unique-amount matching — each order gets a unique paise offset, so incoming payments map to orders automatically
Android notification-reader detector — a companion app reads bank notifications and confirms payments in real time, no bank API or scraping needed
Merchant dashboard — orders, payment status, callbacks, API keys
Webhook callbacks — merchant sites get instant payment confirmation

Architecture

Node.js + Express + SQLite behind nginx, managed by PM2. The detector app talks to the backend over an authenticated API. Zero external payment-provider dependency.