Path movers are among the more complicated things to add to OpenPathSampling. This is because path movers may involve multiple classes. Typically, a new path mover includes at least one PathMover subclass. But most also include a MoveStrategy subclass, and some include a specialized MoveScheme subclass.

We recommend putting all these class definitions in the same file. The easiest way to learn how to implement something is to have a complete example of something similar, and by keeping all the relevant code together, your contributions can be good examples for future contributors.

Then you can import the relevant classes into the correct subpackage handlers. Your subclass of PathMover (and any associated helper classes) should be imported into pathmovers/__init__.py. If you have a MoveStrategy subclass that should be publicly exposed, you should import it into pathmovers/move_strategies.py. If you have a MoveScheme subclass to expose, import it into pathmovers/move_schemes.py. The classes that you expose in this way will be automatically exposed in the root openpathsampling namespace (or openpathsampling.strategies, in the case of MoveStrategy subclasses).