Implementation overview

The primary user-facing component is the gmx Python module, which is implemented in pure Python for consistency, transparency, and maintainability. It’s purpose is to provide an idiomatic and stable interface to the API functionality.

Where functionality and behavior should mirror that of the C++ API, the Python module refers to the sub-package gmx.core, which is a C++ extension that serves as a minimal wrapper to libgmxapi. The bindings in gmx.core are written entirely in C++ using pybind11, a template header library, to be easy to maintain along side the GROMACS C++ API.

Wrapper code in gmx.core is contained in the gmxpy C++ namespace. The gmxpy namespace contains implementation details only and should not be used in other projects. It is documented internally with doxygen syntax.

Wrapper code should only require linking to libgmxapi (not libgromacs). Compilation should only require the public gmxapi headers. The Python package CMake configuration uses gmxapi_DIR or GROMACS_DIR to find the Gromacs::gmxapi CMake target provided by the GROMACS installation.

The gmxapi library is provided in GROMACS 2019 and in a separate GROMACS fork at