Due to their intrinsic complexity, the development of distributed systems is difficult in general and therefore relies on careful and systematic development steps. This paper addresses the design and implementation of distributed systems, using SDL as the design language. In particular, the refinements during implementation design are examined, and it is shown how SDL interfacing patterns can support these steps, even in a heterogeneous environment. Then, tool support to automatically implement the interfacing patterns by generating tailored APIs for the system environment is presented. Finally, these technologies are illustrated in the context of a comprehensive development of a distributed light control system in a heterogeneous environment, using various communication technologies.