Modeling constraints improves software architecture design reasoning

Requirements and project-related factors influence architectural design in intricate and multivariate ways. We are only beginning to understand some of the tacit but fundamental mechanisms involved in reasoning about design decisions, and one of them concerns the role of design constraints. This paper examines design constraints and how they shape design solutions. We introduce a design constraint model and an architectural design reasoning process for specifying design constraints and checking for design conflicts. We experiment with using logic for constraint verification with the Alloy tool.