Which is &quot;for widespread libraries, the choices are basically C, C++, and <i>now (hopefully) rust</i>.&quot;: as in C++ you can use high-level constructs internally without relying on an extensive runtime, and expose and easy-to-FFI C interface.<p>Rust still has insufficiencies though, the inability to customise the (library&#x27;s) allocator is one I think.