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A Rigourous Environment for Development of Concurrent Systems

We present a theorem prover based environment which supports compositional refinement of action systems. Our emphasis is on the stepwise refinement of action system interfaces. This allows us to consider stepwise refinements of action systems as a component-oriented development. Our tool is an extension of the Refinement Calculator which is based on the window inference style of reasoning. Hence, we also describe the extensions of the HOL window inference tool, developed to support action system refinement but also applicable in a broader context.