CSN-01openbank.usProduction2025

Openbank US

Web payments and onboarding for Santander's digital bank

I built the web payments and transfer flows for Openbank's US launch, a Santander Group digital bank. Every mutation is idempotent and traceable before it is confirmed, and the UI state never leads the backend. The result is a bank product that shipped fast without ever shipping wrong.

Role: Frontend Engineer
Client: Santander Group
Category: Banking & Payments
Headline figure: $11B

Open live system

Openbank US — HeroVerified

US deposits since launch: $11B
customers: 100,000+

Problem

Money movement where a single bug becomes a headline. The challenge was shipping quickly without ever shipping a wrong transaction.

Solution

Idempotent transfer flows and an audit-first data model where every mutation is traceable before confirmation. UI state never leads the backend.

Capabilities shipped

Idempotent transfers
Every money-movement mutation is safe to retry without duplication.
Audit-first data model
Mutations are traceable before they are confirmed.
Backend-led UI state
The interface never anticipates what the server has not confirmed.
Accessible banking
Keyboard and screen-reader support for high-stakes financial flows.