Abstract This paper describes the design, implementation, and performance of ES‐Kit, a distributed object‐oriented system being developed by the Experimental Systems Project at the Microelectronics and Computer Technology Corporation. The operating system consists of a kernel and a set of Public Service Objects which dynamically extend the functionality of the kernel by providing several traditional operating system services when required by application objects. Applications for the ES‐Kit environment are written in GNU C++ and do not require additional language primitives for distributed execution. Initial performance results from a representative set of applications indicate that the object‐oriented paradigm provides a powerful solution to distributed programming.

A future provides the basic primitive through which a user in an object-oriented distributed system can achieve concurrency. It is based on the notion of being able to translate what appears to be a remote procedure call into a request for computation to be scheduled by the system. The mechanism required to make this translation is discussed. Refinements to the future mechanism allow futures to be passed as arguments to other procedure calls. This provides the user with the added flexibility of implementing synchronization schemes suited to specific needs. Further, it simplifies the process of migrating an object which has outstanding futures at the time of migration.