Wouldn’t call myself an expert in either, but I think 2 things stand out far more than anything else: 1. Rust is effectively as strict as can be in terms of ownership. In Zig you can just allocate some memory and then start slinging pointers (or slices) all over. If you’re doing this then you’re presumably doing it for mutability and you don’t strictly know where that pointer ends up once you’ve passed it on. 2. Rust’s metaprogramming is split among a couple different things (e.g. traits, macros), whereas Zig’s is unified (comptime). comptime is (at least advertised as) “just normal Zig code” and Rust macros are a great example of “this doesn’t work at all like the base language”.

#1 boils down to “can the LLM solve the pointer aliasing here?” and #2 is translating between metaprogramming paradigms. Could work but a line-by-line translation is a pipe dream.

Zig doesn't have a borrow checker. It's basically C, if C had been much better designed.

Line-by-line ports to idiomatic Rust are usually not possible because of the borrow checker and Rust's ownership rules. That's the reason the Typescript compiler was ported to Go instead of Rust.