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250 C files were deleted. 2032 to go. Watching Zig slowly eat libc from the inside is one of the more satisfying long term projects to follow
That's something I've always admired about Zig.
A lot of languages claim to be a C replacement, but Zig is the second language I've seen that seemed like it had a reasonable plan to do so at any appreciable scale. The language makes working with the C ABI pretty easy, but it also has a build system that can seamlessly integrate Zig and C together, as well as having a translate-c that actually works shockingly well in the code I've put through it.
The only thing it didn't do was be 99% compatible with existing C codebases...which was the C++ strategy, the first language I can think of with such a plan. And frankly, I think Zig keeping C's relative simplicity while avoiding some of the pitfalls of the language proper was the better play.
D can import C files directly, and can do C-source to D-source translation.
D can compile a project with a C and a D source file with:
dmd foo.d bar.c
./fooDoes this mean long term Zig won’t run on OpenBSD?
Because doesn’t OpenBSD block direct syscalls & force everything to go through libc.
This affects static libc only. If you pass -dynamic -lc then the libc functions are provided by the target system. Some systems only support dynamic libc, such as macOS. I think OpenBSD actually does support static libc though.
> I think OpenBSD actually does support static libc though.
How does that work, with syscalls being unable to be called except from the system’s libc? I’d be a bit surprised if any binary’s embedded libc would support this model.
This is very exciting for zig projects linking C libraries. Though I'm curious about the following case:
Let's say I'm building a C program targeting Windows with MinGW & only using Zig as a cross compiler. Is there a way to still statically link MinGW's libc implementation or does this mean that's going away and I can only statically link ziglibc even if it looks like MinGW from the outside?
This use case is unchanged.
If you specify -target x86_64-windows-gnu -lc then some libc functions are provided by Zig, some are provided by vendored mingw-w64 C files, and you don't need mingw-w64 installed separately; Zig provides everything.
You can still pass --libc libc.txt to link against an externally provided libc, such as a separate mingw-w64 installation you have lying around, or even your own libc installation if you want to mess around with that.
Both situations unchanged.
That's cool. I imagine I could also maintain a MinGW package that can be downloaded through the Zig package manager and statically linked without involving the zig libc? (Such that the user doesn't need to install anything but zig)
That's a good way to sell moving over to the zig build system, and eventually zig the language itself in some real-world scenarios imo.
do you suspect it will be possible to implement printf??
while we're talking about printf, can i incept in you the idea of making an io.printf function that does print-then-flush?
That just reminds me anyone know whether rust has something similar? Not wanting to start any Rust v. Zig debate. I am just wanting to be even more independant when it comes to some of my Rust projects.
There is a couple libc implementations:
- c-ward [0] a libc implementation in Rust
- relibc [1] a libc implementation in Rust mainly for use in the Redox os (but works with linux as well)
- rustix [2] safe bindings to posix apis without using C
[0]: https://github.com/sunfishcode/c-ward
realy cool thank you
Cool idea, for sure, but I can't help but wonder: for the code that's been ported, is there a concern that you'd have to perpetually watch out for CVEs in glibc/musl and determine if they also apply to the Zig implementations?
Yes but we already have to do that for our own standard library. For shared codepaths (e.g. math) it's strictly fewer potential bugs.
"Furthermore, when this work is combined with the recent std.Io changes, there is potential for users to seamlessly control how libc performs I/O - for example forcing all calls to read and write to participate in an io_uring event loop"
This is exciting! I particularly care more about kqueue but I guess the quote applies to it too.
> It’s kind of like enabling LTO (Link-Time Optimization) across the libc boundary, except it’s done properly in the frontend instead of too late, in the linker
Why is the linker too late? Is Zig able to do optimizations in the frontend that, e.g., a linker working with LLVM IR is not?
Seems like it ought to be able to do inlining and dead code stripping which, I think, wouldn't be viable at link time against optimized static libraries.
It is viable against the IR that static libraries contain when LTO is enabled.
LTO essentially means “load the entire compiler backend into the linker and do half of the compilation work at link time”.
It’s a great big hack, but it does work.
There are so many scary parts of libc, this is a really exciting project
There are many useful functions too. Like "memfrob" and "strfry". I hope the Zig libc makes those available too
Just joking of course. Those are sadly only in glibc.. :)
Does anyone know if there is a timeline on when Zig might achieve 1.0? I've been interested in the language for a while, but I'm a bit concerned about writing anything important in it when it seems to be evolving so much at the moment
Nobody knows, but for what it's worth, existing large projects that are used in production environments have been fairly good at keeping up with Zig releases. See: Bun, Ghostty, and Tigerbeetle for good examples of this. Because the semantics of Zig are relatively simple, porting to the latest version is usually as simple as bumping your compiler version, trying to build, making a fairly mindless, mechanical change, and repeating until it builds.
The biggest thing holding me back from using Zig for important projects is the willingness of my peers to adopt it, but I'm just building projects that I can build myself until they are convinced :)
There's no timeline for 1.0
You might find this interesting: https://www.youtube.com/watch?v=x3hOiOcbgeA
I’m sure this has crossed someone’s mind but why isn’t this called zlibc? :-)
I rather like "libz".
Not to be confused with zlib.
Perhaps to avoid confusion with zlib?
Super cool project.
I expect a lot of C code may be quite mechanically translated to Zig (by help of LLMs). Unlike C->Rust or C->C++, where there's more of a paradigm shift.
There's solid reason for the translation here; the Zig core team is aiming to eliminate duplicated code and C functions, and avoid the need to track libc from multiple sources. In the future, LLMs could serve as part of this, but they are currently quite terrible at Zig (as far as I understand it, it's not a lack of Zig code samples, it's an imbalance of OLD Zig to NEW Zig, as Zig changes quite frequently).
You would need to consider if it is even worth it translating your C code. If the paradigm is identical and the entire purpose would be "haha it is now one language," surely you could just compile and link the C code with libzigc... In my opinion, it's not worth translating code if the benefit of "hey look one language" requires the cost of "let's pray the LLM didn't hallucinate or make a mistake while translating the code."
Does Zig does have the man power to keep these up to date?
I think we either need to make operating systems not in C, or just accept that at some level we rely on C.
Not C. PDP-11
"Abolish ICE" at the bottom. Obviously a Bad Bunny fan, as I am.
The very same day I sat at home writing this devlog like a coward, less than five miles away, armed forces who are in my city against the will of our elected officials shot tear gas, unprovoked, at peaceful protestors, including my wife.
https://www.kptv.com/2026/01/31/live-labor-unions-rally-marc...
This isn't some hypothetical political agenda I'm using my platform to push. There's a nonzero chance I go out there next weekend to peacefully protest, and get shot like Alex Pretti.
Needless to say, if I get shot by ICE, it's not good for the Zig project. And they've brought the battle to my doorstep, almost literally.
Abolish ICE.
I too am sick of internal compiler errors
I too am sick of internal combustion engines, a product of the last century.
I too am sick of intrusion countermeasures electronics. Think of all the poor netrunners out there.
Well, I guess the Zig project is now writing in NTSC, causing compatibility issues for the PAL folks out there.
/s
This strikes me as a very agent-friendly problem. Given a harness that enforces sufficiently-rigorous tests, I'm sure you could spin up an agent loop that methodically churns through these functions one by one, finishing in a few days.
hallucinations in a libc implementation would be especially bad
Have you ever used an LLM with Zig? It will generate syntactically invalid code. Zig breaks so often and LLMs have such an eternally old knowledge cutoff that they only know old ass broken versions.
The same goes for TLA+ and all the other obscure things people think would be great to use with LLMs, and they would, if there was as much training data as there was for JavaScript and Python.