Abstract: The simulation of all-atom molecular dynamics is restricted in both length (~nm) and time (ps~ns) scales, limiting its application in modeling microstructure evolution (nm~μm) in hard crystals or conformation dynamics in soft polymers (ns~ms).  We turn to modeling coarse-grained molecular dynamics, using approximate, non-Markovian representations of less relevant degrees of freedom. The equations of motion for these effective models can be derived from all-atom simulation data. We will present a few examples and introduce relevant open-source packages.