I guess there are different levels of meta-programming. You can go really far in Rust/C++ too but I think Zig is really unique that you can write a function, which takes a type, it does some imperative mumbo-jumbo and spits out another type, doing exactly what you want, without having to think about restrictions, trait bounds, or whatever.

For example, here's comptime dependency-injection container, which notably, can be configured and extended, completely in comptime, and the final glue is something which in theory the compiler could optimize away too (no idea if it does). https://github.com/cztomsik/tokamak/blob/main/src/container....

And regarding what they discuss in article, I did something similar for N-API, note how much you can do in few hundred lines, and I'd say that you can use it for most of what people do with napi-rs except that napi-rs is huge (and also unsafe, because it allows indirect recursion, which allows breaking all the rustc promises) https://github.com/cztomsik/napigen/blob/main/src/napigen.zi...