The Elements.MEP library is designed to support the creation of MEP systems. It is a work in progress that has been used for production work but should be considered a beta release. It is built on top of the Elements library.
There are sample Interactive Notebooks that demonstrate some key capabilities of the library and how it is meant to be used.
Conceptual overview of the library can be found here: https://docs.hypar.io/hypar-mep