  Molecular dynamics (MD) simulations represent a powerful investigation tool
in the field of soft matter. By using shear flows, one can probe the bulk
rheology of complex fluids, also beyond the linear response regime, in a way
that imitates laboratory experiments. One solution to impose a shear flow in
particle-based simulations is the Lees-Edwards technique which ensures that
particles experience shear by imposing rules for motion and interactions across
the boundary in the direction of the shear plane. Despite their presentation in
1972, a readily available public implementation of Lees-Edwards boundary
conditions has been missing from MD simulation codes. In this article, we
present our implementation of the Lees-Edwards technique and discuss the
relevant technical choices. We used the ESPResSo software package for Molecular
Dynamics simulation of soft matter system, which can be used as a reference for
other implementers. We illustrate our implementation using bulk dissipative
particle dynamics fluids, compare different viscosity measurement techniques,
and observe the anomalous diffusion in our samples during continuous and
oscillatory shear, in good comparison to theoretical estimates.
