Cling-based Python-C++ bindings
cppyy provides fully automatic, dynamic Python-C++ bindings by leveraging the Cling C++ interpreter and LLVM. It supports both PyPy (natively), CPython, and C++11/14/17.
Details and performance are described in this paper, but note that the CPython performance has been vastly improved since that conference.
Full documentation: cppyy.readthedocs.io.
Notebook-based tutorial: Cppyy Tutorial.