Packaging for Use by Other Languages
In general, you compile a .so (shared library) file that other languages can call through FFI. If you need to allow replacing the .so at runtime, you must keep the ABI stable. The simplest approach is to expose a C API. Another option is to use SWIG, but it is usually difficult to ensure ABI compatibility this way. Without ABI compatibility, you can't just swap the .so; you have to rebuild your project.