Based on the articles I've read on wikipedia and other sources, I've learnt that operating systems like the ones based on UNIX implement the POSIX-API in C. Moreover, I'm yet to find a POSIX-compliant operating system that implements the POSIX-functionalities in any language other than C.
So, does the POSIX-standard require it's specifications to be implemented in the C language only? Can someone implement the POSIX-functionalities for their own(self-made) operating systems in any other programming language like (pure)Rust and get that operating system certified as a POSIX-compliant OS?