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Northstar Pay
UPI-first payments app with instant settlements, split bills and a ledger backend built for scale.
The challenge
A payments startup needed a consumer app and a ledger that could settle instantly and pass a bank partner’s security review.
What we built
- 1
UPI-first mobile app with split bills, requests and instant settlement.
- 2
Double-entry ledger service with idempotent APIs and full audit trail.
- 3
Penetration testing and a security review passed before launch.
- 1.2M
- transactions in month one
- 99.98%
- uptime
- 0
- reconciliation breaks
Stack
- React Native
- Go
- PostgreSQL
- AWS
Sample case study. Swap in real screenshots, numbers and a client quote before launch.