One thing I wish Rust would improve over time is the builds. Its one of the biggest sources of wasted storage space on all my computers, builds a ton of libraries can take tens of gigs, it adds up very quickly. Not sure what the best solution is, one I found is to set the global build folder so dependencies get reused across projects, but imho it should be an OOTB default behavior whatever the real solution should be.
How Our Rust-to-Zig Rewrite Is Going
31–40 of 336 posts
Re: How Our Rust-to-Zig Rewrite Is Going
#32Earlier quoted context omitted.
Layperson here: what is special about Go's runtime, aside from the GC?
It's literally the most sophisticated scheduling engine in the world. In practice, Go can typically outperform Rust in throughput (using more memory), despite having a mountain of disadvantages against it in theory. That's how good the Go scheduler/runtime is.
> It's literally the most sophisticated scheduling engine in the world.
That seems unlikely regardless of how good it is. This is a domain where state-of-the-art research is not in the public literature. Scheduling is an AI-complete problem.
Re: How Our Rust-to-Zig Rewrite Is Going
#33Earlier quoted context omitted.
One of the primary goals for the Roc project is compiler speed. I presume OCaml is out of the running because it's not a systems language.
OCaml compiler is incredibly fast. I wonder how it'd fare with Jane Street's extensions for the borrow checker etc in OxCaml, if it's good enough for their HFT I'm sure it's good enough for a new language.
I wrote a toy Scheme implementation in OCaml by using the Camplp4 preprocessor. In benchmarks, it was faster than Gambit Scheme, which compiles through C.
Re: How Our Rust-to-Zig Rewrite Is Going
#34Zig's incremental builds are DEFINITELY a killer feature. In the short term, I could see why you'd make a switch to get it. But, in the medium term, can we really not expect to see this in Rust in the somewhat near future? I want to go fast, but I don't want to go fast just to shoot my foot off. If only somehow we could get Rust's safety with all of Zig's features and Go's runtime without GC... That's what I'm workin…
This is being worked on:
https://rust-lang.github.io/rust-project-goals/2026/roadmap-...
Most of the goals on this page are targeted for this year.
Re: How Our Rust-to-Zig Rewrite Is Going
#35I think this is a fine post. But one comment: > remember that for compilers which emit machine code, like roc and rustc, doing memory-unsafe things is a big part of the job I don't really think that this is true, in the way that it's written. I think that for the hot binary patching / code reloading features, yes, that is going to need unsafe. But for regular old "producing an executable" compilation? Emitting machin…
I think if you interpret it charitably it means that any bug in the emitted machine code is already a likely memory-unsafe miscompilation if it is ran.
The compiler itself might be perfectly "memory safe" but the generated binary fundamentally is always at risk (besides WebAssembly I suppose).
I'm fully aware of the separation of compiler and binary, and being able to compile untrusted code safely is nice, but a perfectly safe compiler that generates vulnerable binaries isn't that much better.
Re: How Our Rust-to-Zig Rewrite Is Going
#36One thing I wish Rust would improve over time is the builds. Its one of the biggest sources of wasted storage space on all my computers, builds a ton of libraries can take tens of gigs, it adds up very quickly. Not sure what the best solution is, one I found is to set the global build folder so dependencies get reused across projects, but imho it should be an OOTB default behavior whatever the real solution should be…
I always got a kick out of that, coming from a JavaScript background where people constantly harp on the size of node modules.
My Tauri project, where the backend is much smaller code-wise than the frontend, has 9gb of rust artifacts (node_modules is 550mb for comparison)
Re: How Our Rust-to-Zig Rewrite Is Going
#37Zig's incremental builds are DEFINITELY a killer feature. In the short term, I could see why you'd make a switch to get it. But, in the medium term, can we really not expect to see this in Rust in the somewhat near future? I want to go fast, but I don't want to go fast just to shoot my foot off. If only somehow we could get Rust's safety with all of Zig's features and Go's runtime without GC... That's what I'm workin…
Instead of waiting for faster compiler in Rust, how about from the other direction, adding some kind of borrow checker to Zig? That sounds more within reach and practically achievable, possibly even in userland.
It's impossible to add a borrow checker to any existing language.
The reason Rust has a working borrow checker is because every part of the language from structs, enum, traits, generics and all the way to the syntax itself has been designed to support lifetimes and borrow checking.
It's is not something you can just tack on to an existing language without fundamentally changing it.
Re: How Our Rust-to-Zig Rewrite Is Going
#38I think this is a fine post. But one comment: > remember that for compilers which emit machine code, like roc and rustc, doing memory-unsafe things is a big part of the job I don't really think that this is true, in the way that it's written. I think that for the hot binary patching / code reloading features, yes, that is going to need unsafe. But for regular old "producing an executable" compilation? Emitting machin…
> I think that for the hot binary patching / code reloading features, yes, that is going to need unsafe. But for regular old "producing an executable" compilation? Emitting machine code isn't the part that requires unsafe. The language's runtime is a more likely site to find unsafe.
Agreed! Emitting machine code is not unsafe, since it's just writing bytes down - it's only once you execute that machine code that there's potentially unsafety. The reason I said "a big part of the job" is that in practice a lot of compilers both emit machine code and execute it - but you're totally right that it's not a requirement that a compiler do both.
In addition to the examples you gave (hot binary patching/code reloading, language runtime, etc.), others would be things like evaluating userspace code at compile time (e.g. const fn in Rust, or in Roc any expression that could be hoisted to the top level), running tests and inspecting their output to decide what to display to the user, etc.
Those are the types of things I had in mind when I wrote that.
Re: How Our Rust-to-Zig Rewrite Is Going
#39I think this is a fine post. But one comment: > remember that for compilers which emit machine code, like roc and rustc, doing memory-unsafe things is a big part of the job I don't really think that this is true, in the way that it's written. I think that for the hot binary patching / code reloading features, yes, that is going to need unsafe. But for regular old "producing an executable" compilation? Emitting machin…
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Re: How Our Rust-to-Zig Rewrite Is Going
#40Earlier quoted context omitted.
Layperson here: what is special about Go's runtime, aside from the GC?
It's literally the most sophisticated scheduling engine in the world. In practice, Go can typically outperform Rust in throughput (using more memory), despite having a mountain of disadvantages against it in theory. That's how good the Go scheduler/runtime is.
What benchmarks are you referring to?
Rust itself doesn't have a scheduler of course, I assume this is comparing against tokio or one of the other async executors?