On using a Composition Principle toDesign Parallel

We brieey present a rigorous and modular method, we are developing to design concurrent systems starting from their desired properties. This method is based on a mechanization of Manna-Pnueli's modular validity concept and on a modular temporal language in which properties are invariant under stuttering 1]. A compositional proof system is established to support both speciication veriica-tion and modular program construction. Each program is developed together with the proof that it meets its speciication. A reenement relation is deened by using rules in backward, while the proof is constructed by using the same rules in forward. Constrained by a limited space, we focus attention on the underlying concepts and leave a complete presentation of the proof systems (soundness, relative completeness, modular completeness, and adaptation completeness) in a future paper.