Occasionally, people write code to allow c or c++ code to call code in a higher-level language, perhaps in an embedded interpreter. In that case, using the native-code tag feels wrong, since we're going in the opposite direction. The best way to tag such questions, I believe is ffi, a tag that I have just created. A foreign function interface is a mechanism by which a program written in one programming language can call routines or make use of services written in another.
If we have a ffi tag, though, then native-code is just a special case of FFI, right? Whether high-level code calls low-level code or vice versa, it's a similar topic and skillset, I think. Should we rename native-code to ffi for generality?