A unified wallet manager (UWM) virtualized as a single virtual service in which all transactions relative to the UWM are treated as immutable facts permanently stored in append-only queues or ledgers from the time of their creation. A rules engine reads conversion requests in request calls to the service, and determines which rule or rules to apply to convert funds from one ledger to another, in the same or different vertically scaled gaming systems. The UWM is a peer of other vertical gaming systems, and the gaming systems access the UWM via an API server and data egresses from the UWM through an ETL process from a database cluster. The immutable queues allow for data reconstruction using any desired data model. The ledger stores funds of many different types, including real money, points, play money, and others. Third parties can integrate with the UWM through an integration hub connected to the UWM.