1. A computer-implemented method that provides a customized user experience for a computing system, the method comprising: storing a user experience markup language file, the user experience markup language file comprising one or more markup tags that generate a user interface comprising one or more user interface objects, and one or more markup tags referencing an application programming interface (API) that accesses functionality exposed by a computer program; and executing a user experience platform engine on the computing system that processes the user experience markup language file to render the one or more user interface objects, the user experience platform engine operative to determine that the user experience markup language file has at least one markup tag of the one or more markup tags contained therein referencing the API that accesses functionality exposed by the computer program, and in response thereto, to call the API to utilize the functionality exposed through the API by way of the user interface.