In this paper, the authors present a middleware platform, Prottoy for the development of smart object systems. A smart object has some specific characteristics e.g., augmentation variation, perceptual feedback provision, push-pull model, etc. In addition a smart object could be stand-alone, co-operative or associated with an external application. Generic pervasive middlewares have no clean support for accommodating all these characteristics of smart objects. Prottoy is designed by carefully observing the characteristics of smart objects and it has taken a core-cloud approach to represent them digitally. A smart object's common functional features are combined together as a generic core and a collection of supplementary service profiles represents the cloud that can be plugged-in atop the core.