νZ — An Optimizing SMT Solver. νZ is a part of the SMT solver Z3. It allows users to pose and solve optimization problems modulo theories. Many SMT applications use models to provide satisfying assignments, and a growing number of these build on top of Z3 to get optimal assignments with respect to objective functions. νZ provides a portfolio of approaches for solving linear optimization problems over SMT formulas, MaxSMT, and their combinations. Objective functions are combined as either Pareto fronts, lexicographically, or each objective is optimized ndependently. We describe usage scenarios of νZ , outline the tool architecture that allows dispatching problems to special purpose solvers, and examine use cases