When general force field parameters are inaccurate for a particular molecule, bespoke parameters can be fit specifically for the molecule in question . Recently introduced bespoke force field fitting tools allow parameters for both small molecules and proteins to be fit from quantum mechanical calculations before running simulations . The energy barrier for bond rotation can be affected by the chemical environment many bonds away, making bespoke torsion fitting in combined with parameters from general force fields a common practice . In any of these scenarios, it would be useful to be able to store and reuse these parameters again. ChemPer's SingleGraph can be used to create SMIRKS patterns where the whole molecule is specified with the atoms tagged for the relevant parameter. These parameters and SMIRKS could be added to the end of a SMIRNOFF file. Since parameters are assigned hierarchically and the bespoke SMIRKS would match only the specific molecule this SMIRNOFF could be used to parameterize the relevant molecule without affecting parameters assigned to other molecules in the system.