You download a neo-bank app. You type in your name, date of birth, and Social Security Number. You take a quick video selfie. Three seconds later, the screen flashes green: Account Approved. From the user’s perspective, this is a seamless,…
One of the first principles we adopted after decomposing the system was simple: Every service should own its own data. It sounded right. The architecture became cleaner. Teams could deploy independently. Services no longer needed direct access to another service’s…
In a traditional bank, a payment card is a physical artifact tied to a pre-allocated ledger state. You apply for a card. The bank’s underwriting system reviews your credit, allocates a $5,000 credit limit on your account row, orders a…
The transaction used to be simple. At least, it looked simple from the application’s perspective. A customer placed an order. The system processed the payment. The order was created. Inventory was reserved. The ledger was updated. The customer received a…
In a traditional bank, the core ledger is a single-tenant monolith. The database instance belongs entirely to one legal entity. If a query returns a bad row, the blast radius is contained within that bank’s own customers. Banking-as-a-Service (BaaS) destroys…
The system was becoming increasingly difficult to change. Every time we added a new capability, another service needed to know about it. A payment completed. The ledger needed to update. Notifications needed to be sent. Fraud analytics needed the transaction.…
