purushotentitle/NexSwitch ? reverse-engineered prompt

Build me a production style Indian payment switch and merchant platform that can handle card payments and UPI end to end.

I want a backend that can accept ISO 8583 traffic over a persistent TCP connection, validate and route transactions, do cryptography for ARQC and PIN block handling with an HSM style setup, score fraud in real time, and then run settlement and three way reconciliation jobs later in the day. It should also support dynamic UPI QR generation, reversals, chargebacks, webhooks, and an audit friendly transaction history.

Please make it feel like a real internal payments system, with a clean separation between core business logic and infrastructure, and include a few web dashboards for a payment simulator, merchant view, ops view, and a QA view. Use sensible defaults, add good tests, and if you need current library details, look up the latest docs online before wiring it up.