That's true, though systems programming is in practice dominated by the C ABI (great post on that here by the way https://drewdevault.com/2020/03/03/Abiopause.html). Zig does something quite special that puts it ahead of the crowd in this space; It can import and use C libraries as easily as C does (no bindings required), and it can itself be built into a C library, auto-generating the required C headers.