In this short paper, a unified framework for solving Boolean, integer and set constraints is presented. The computation model for solving conjunctions of primitive constraints, possibly with existential and universal quantifications, is described using rewrite rules. An important feature of the constraint solving model is that a variable's domain (set of integers) can be a constrained variable ({\sl set variable}). Based on such a strong extension, set constraints and dynamic constraints are introduced. Integer constraints, Boolean logic and set reasoning are combined perfectly in a single constraint solver.