In addition to these utilities, a number of example calculation scripts are included, as well as comprehensive unit tests, documentation, and tutorials, all within a MolSSI cookiecutter, which we found at . Within the API, it is possible to define a milestone as a type from a growing list of possible shapes. While all the milestones in this study are concentric spheres, it is also currently possible in SEEKR2 to connect milestones of non-concentric spherical shapes, planar milestones, milestones that are a linear, weighted function of distances, angles, and dihedral order parameters, and milestones that depend on the RMSD of a set of atoms to a reference structure. Simple examples of API usage may be found at .