Simulation-based design optimization has been steadily maturing over the past two decades, but not without its own unique and persistent challenges. The proposed project will develop a novel solution to one of the long-standing bottlenecks in simulation-based design optimization. Particularly, we will develop a flexible geometry toolkit for shape parameterization and modification as required for design optimization. With our discrete geometry toolkit, shape modifications will be achieved via an elegant and intuitive "plug-and-play" approach, providing engineers with a wide variety of options for shape parameterization, shape deformation, and geometric constraint imposition. Our geometry toolkit will be composed of independent modules and will be easily integrated into existing or future analysis and design environments. Our approach will offer a modular and intuitive means to interactively synthesize appropriate modifications to discrete geometry shapes in a design optimization setting including the specification of geometric constraints and interdisciplinary data transfer.