Pychoco
Python bindings for the Choco Constraint programming solver (https://choco-solver.org/).
Choco-solver is an open-source Java library for Constraint Programming (see https://choco-solver.org/). It comes with many features such as various types of variables, various state-of-the-art constraint, various search strategies, etc.
The PyChoco library uses a native-build of the original Java Choco-solver library, in the form of a shared library, which means that it can be used without any JVM. This native-build is created with GraalVM (https://www.graalvm.org/) native-image tool.
We heavily relied on JGraphT Python bindings (https://python-jgrapht.readthedocs.io/) source code to understand how such a thing could be achieved, so many thanks to JGraphT authors!