A Refinement Driven Component-Based Design

Modern software applications ranging from enterprise to embedded systems are becoming increasingly complex, and require very high levels of dependability assurance. The most effective means to handle complexity is separation of concerns and incremental development, and assurance of dependability requires formal methods. We report here our experience on these issues in an application of a formal calculus, rCOS, to a component-based design of the point of sale system (POS). We demonstrate the possibility in scaling-up correctness by design and discuss how rCOS may be integrated with current and emerging software engineering tools.