Task Computing computer system by segmenting the system into a plurality of implementation tiers of a presentation layer, a remote procedure call programming interface (API), a middleware layer to which the presentation layer interfaces via the remote procedure call API to real-time, dynamically generate a computer implemented task interface at the presentation layer to a semantically described source of function as a service on a computer system, and a service layer and a function source realization layer providing the semantically described source of function as the service on the computer system to which the middleware layer interfaces. Real-time and dynamically composing an executable task that comprises one or more services using the generated task interface at the presentation layer to one or more services on the computer based upon the semantically described application-, device- and service-rich computer.