Payback Billing
Architect & lead engineer
A multi-tenant billing and business-operations platform serving multiple businesses from one system, owned from first architecture decision through to live operation.
- Runs the full commercial cycle — clients, subscriptions, invoicing, multi-currency pricing, purchasing, inventory, staff and support.
- Every business's data and permissions kept fully separate, with access control built once and inherited everywhere.
- Stays responsive under load: long-running jobs and large uploads process in the background with live progress reporting.
- Deployed on AWS and migrated between hosting providers with no data loss and minimal downtime.