The City of Buenos Aires Tax Department had the challenge of unifying all existing tax systems by Individual accounts (or
CUIT in Argentina).
To achieve that we created a Services Platform over a Service-Oriented Architecture, along with a thin web client. The services layer used Web Services to expose the underlying business logic, which was made up of pre-existing COBOL programs. The web client we built was a thin layer that would only be responsible for presenting the results in a clear and concise way.
The unified Tax Platform ended up being composed of a multitude of services covering hundreds of scenarios, providing extremely valuable information to tax contributors. The platform is currently processing over 150k transactions a day, with peaks of 50k per hour.