From Process Calculi to Klaim and Back

We briefly describe the motivations and the background behind the design of Klaim, a process description language that has proved to be suitable for describing a wide range of distributed applications with agents and code mobility. We argue that a drawback of Klaim is that it is neither a programming language, nor a process calculus. We then outline the two research directions we have pursued more recently. On the one hand we have evolved Klaim to a full-fledged language for distributed mobile programming. On the other hand we have distilled the language into a number of simple calculi that we have used to define new semantic theories and equivalences and to test the impact of new operators for network aware programming.