%T Developing an optimising compiler for occam %A Spiridon Kalogeropoulos %E Peter H. Welch, Andr\[`e] W. P. Bakkers %B Proceedings of WoTUG\-21: Architectures, Languages and Patterns for Parallel and Distributed Applications %X occam is a high\-level language which got constructs for generating explicitly concurrent processes which communicate using channels. In this paper we present our methodology for developing an optimising occam compiler which consist of a framework to represent concurrency and the semantic properties of an occam program that enables efficient process optimisations, and inter\-procedural optimisations to be performed. Furthermore, we tackle the issue of retargeting the optimising occam compiler for different processors of the transputer family.