An executable computational logic can provide the desired bridge between formal system properties and formal methods to verify them on the one hand, and executable models of system designs based on programming languages on the other. However, not all such logics are equally well suited for the task. This paper gives some requirements that seem important for a computational logic to be suitable in practice, and discusses the experience with rewriting logic, its Maude language implementation, and its formal tool environment, concluding that they seem to meet well those requirements.