WaveQLab3D is a code for 3D seismic wave propagation and earthquake rupture dynamics. It solves the elastic wave equation in curvilinear coordinates (i.e., complex geometries) with a possibly nonplanar frictional fault interface. The current version supports off-fault viscoplasticity, spatially variable elastic properties, and several friction laws (including rate-and-state and slip-weakening). The code is under development and is available under the MIT license. Authors include Kenneth Duru, Sam Bydlon, Eric Dunham, and Kyle Withers with parallelization by Hari Radhakrishnan.