Zig is aiming to be lower level than Rust. As the project homepage prominently advertises, it has no hidden memory allocation or control flow. It also gives more control over how memory is allocated, which is potentially useful in applications with particularly tight performance requirements.
Kelley first created Zig when hr was working on a digital audio workstation and found most existing languages to be awkward for working with particularly hard real time requirements, but still wanted something more modern than C. Im speculating here, but I believe its advantage over Rust for that specific application is that you have tighter control over exactly when memory is allocated and deallocated, and how data is laid out in it. Rust wants to tie allocation lifetimes to scope in a very fine grained way that I would guess is beneficial the vast majority of the time, but does still make it harder to reason about when you’re about to stall out the CPU while the allocator does its thing.
> Zig is aiming to be lower level than Rust.
Zig and Rust are equivalently "low level". Zig isn't any closer to the hardware than Rust is.
> but I believe its advantage over Rust for that specific application is that you have tighter control over exactly when memory is allocated and deallocated, and how data is laid out in it.
Rust gives you all this, too.
Zig's primary (possibly only) advantage over Rust is that it has much faster compilation times.
> it has no hidden memory allocation or control flow
Rust had like 3 allocating types total. If you aren't working with extremely deeply nested 3rd party types it's trivial to identify when allocations happen. Hell you could throw a lint rule together in like 5 minutes to warn on it if you're really worried. Besides Drop (excluding async) is there even any hidden control flow?
> Im speculating here, but I believe its advantage over Rust for that specific application is that you have tighter control over exactly when memory is allocated and deallocated, and how data is laid out in it.
Rust has almost exactly the same semantics for controlling allocations and deallocations, it just prevents you from screwing it up and not freeing something or using the allocation after freeing it. You still have to pass around your reference in your call stack until you no longer need it.
> Rust wants to tie allocation lifetimes to scope in a very fine grained way that I would guess is beneficial the vast majority of the time, but does still make it harder to reason about when you’re about to stall out the CPU while the allocator does its thing.
It's really not substantially different. You allocate ahead of time or don't allocate at all. The only real difference is you might want to use an Option instead of an uninitialized pointer because it's semantically more correct and harder to screw up.