  We present the publicly available moving-mesh hydrodynamics code Sprout.
Sprout solves the equations of ideal hydrodynamics on an expanding Cartesian
mesh. The expanding mesh can follow fluid outflows for several orders of
magnitude with very little numerical diffusion, thereby capturing shocks and
fine structures accurately. Following the bulk flow accurately also allows for
longer timesteps in general. This makes Sprout particularly suitable for
studying expanding outflows such as supernova remnants and active galactic
nuclei. Relative to other moving mesh codes, the simple mesh structure in
Sprout is also convenient for implementing additional physics or algorithms.
Many code tests are performed to test the accuracy and performance of the
numerical scheme.
