  We describe the structure and implementation of a moving-mesh hydrodynamics
solver in the large-scale parallel code, Charm N-body GrAvity solver (ChaNGa).
While largely based on the algorithm described by Springel (2010) that is
implemented in AREPO, our algorithm differs a few aspects. We describe our use
of the Voronoi tessellation library, VORO++, to compute the Voronoi
tessellation directly. We also incorporate some recent advances in gradient
estimation and reconstruction that gives better accuracy in hydrodynamic
solutions at minimal computational cost. We validate this module with a small
battery of test problems against the smooth particle hydrodynamics solver
included in ChaNGa. Finally, we study one example of a scientific problem
involving the mergers of two main sequence stars and highlight the small
quantitative differences between smooth particle and moving-mesh hydrodynamics.
We close with a discussion of anticipated future improvements and advancements.
