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.…
A driver in New York finishes her last trip of the night and closes the Uber app. She opens her banking app. The $15 fare she just earned is already sitting in her checking account, available to spend. Uber does…
You download a modern application with a minimalist interface. You pass your phone camera over your driver’s license, type in your identification details, and seconds later, you have a checking account. You are issued a routing number and an account…
The monolith had become difficult to work with. Deployments were getting larger. Teams were stepping on each other. Some parts of the system needed to scale independently. A small change in one area could require deploying the entire application. The…
You are traveling in France. You sit down at a café and order a coffee. The bill is €5.00. Ten years ago, tapping a standard US-issued debit card would trigger a traditional cross-border flow. The card network would authorize the…
