Status and prospects for SuperKEKB and BEAST (Commissioning Detector)

The Belle II experiment at the SuperKEKB collider in Tsukuba, Japan, will start taking physics data in 2018 and will accumulate 50 $\mathrm{ab}^{-1}$ of e+e- collision data, about 50 times larger than the data set of the earlier Belle experiment. The new detector will use GEANT4 for Monte Carlo simulation and an entirely new software and reconstruction system based on modern computing tools. Examples of physics simulation including beam background overlays will be described.