The first generations of OpenFF force fields (Parsley and Sage ) to be trained using this infrastructure have been released, and show competitive accuracy when estimating quantum chemical conformational energetics, various physical property measurements, and protein-ligand binding free energies. However, until now, there has not been any departure from the commonly-used LJ-based force field functional forms. Here, we introduce smirnoff-plugins as a means to support nonbonded potentials, of arbitrary functional forms, within the OpenFF software stack. We use this new architecture to automate the training of a new, transferable, small molecule DE force field parameter library for use in condensed phase simulations, and demonstrate improvements against the Sage force fields across all condensed phase metrics. We further evaluate the DE force field against experimental transfer free energies between aqueous and nonaqueous solvents, which is a promising surrogate for proteinligand binding, and again demonstrate advantages over the LJ functional form. The final force field is available for use in OpenMM , including support for GPU acceleration. The parameter library, and instructions for use with the Open Force Field Toolkit, are freely available at .