A server system facilitates an exchange of messages with a remote client application. The server system includes a plurality of application servers hosting a plurality of applications. A plurality of Application Program Interfaces (APIs) provides programmatic access to the plurality of applications, each of the APIs being configured to receive request messages compiled by the remote client application. First and second request messages, respectively addressed to first and second APIs of the plurality of APIs by a remote client application, each comprise at least one common data component. Further, the first request message includes a first payload specific to the first API, and the second request message includes a payload specific to the second API.