I would really like to hear from people using Zig in production/semi-serious applications; where software stability is important.
How's your experience with the constantly changing language? How're your update/rewrite cycles looking like? Are there cases where packages you may use fall behind the language?
I know Bun's using zig to a degree of success, was wondering how the rest were doing.
I maintain a ~250K LoC Zig compiler code base [0]. We've been through several breaking Zig releases (although the code base was much smaller for most of that time; Writergate is the main one we've had to deal with since the code base crossed the 100K LoC mark).
The language and stdlib changing hasn't been a major pain point in at least a year or two. There was some upgrade a couple of years ago that took us awhile to land (I think it might have been 0.12 -> 0.13 but I could be misremembering the exact version) but it's been smooth sailing for a long time now.
These days I'd put breaking releases in the "minor nuisance" category, and when people ask what I've liked and disliked about using Zig I rarely even remember to bring it up.
I've worked on two "production" zig codebases: tigerbeetle [0] and sig [1].
These larger zig projects will stick to a tagged release (which doesn't change), and upgrade to newly tagged releases, usually a few days or months after they come out. The upgrade itself takes like a week, depending on the amount of changes to be done. These projects also tend to not use other zig dependencies.
Zig 0.15 is pretty stable. The biggest issue I face daily are silent compiler errors (SIGBUS) for trivial things, e.g. a typo in an import path. I've yet to find exactly why this [only sometimes] causes such a crash, but they're a real pain to figure out over a large changeset. `zig ast-check` sometimes catches the error, else Claude's pretty good at spotting where I accidentally re-used a variable name (again, 90% of the time I do that, it's an easy error, but the other 10%, I get a message-less compiler crash). It sounds like the changes in the OP might be specifically addressing these types of issues.
Also, my .zig-cache is currently at 173GB, which causes some issues on the small Linux ARM VPS I test with.
As for upgrades. I upgraded lightpanda to 0.14 then 0.15 and it was fine. I think for lightpanda, the 0.16 changes might not be too bad, with the only potential issue coming from our use of libcurl and our small websocket server (for CDP connections). Those layers are relatively isolated / abstracted, so I'm hopeful.
As a library developer, I've given up following / tracking 0.16. For one, the change don't resonate with me, and for another, it's changing far too fast. I don't think anyone expects 0.16 support in a library right now. I've gotten PRs for my "dev" branches from a few brave souls and everyone seems happy with that arrangement.
> The biggest issue I face daily are silent compiler errors (SIGBUS) for trivial things, e.g. a typo in an import path.
I don't use zig. My experience has been that caches themselves are sources of bugs (not talking about zig only, but in general). Clearing all relevant caches occasionally is useful when you're experiencing weird bugs.
I don't know why I was downvoted here. One day, I was experiencing weird compilation errors. Clearing the `ccache` C/C++ compiler cache helped get past the problem. Yes, I could have investigated in detail what was the issue and if ccache had a bug but sometimes you don't have the luxury of investigating everything your toolchain throws at you.
> zig's caching system is designed explicitly so that garbage collection could happen in one process simultaneously while the cache is being used by another process.
> I just ran WizTree to find out why my disk was full, and the zig cache for one project alone was like 140 GB.
> not only the .zig-cache directory in my projects, but the global zig cache directory which is caching various dependencies: I'm finding each week I have to clear both caches to prevent run-away disk space
Like what's going on? This doesn't seem normal at all. I also read somewhere that zig stores every version of your binary as well? Can you shed some light on why it works like this in zigland?
AFAIK garbage collection is basically not implemented yet. I myself do `ZIG_LOCAL_CACHE_DIR=~/.cache/zig` so I only have to nuke single directory whenever I feel like it.
20 seconds each time. Last time I tried to enable incremental build, it wasn't working for us. It was a while ago, but I think it had to do with something in our v8 bridge.
The forever backwards compatible promise of C++ was a tremendous design mistake that has resulted in mindshare death as of 2026. It might suck to have to modify your code to continue to get it to work, but it’s the right long term approach.
Mindshare death is a very large overstatement given the massive amount of legacy C++ out there that will be maintained by poor souls for year to come. But you are right, there used to be a great language hiding within C++ if the committee ever dared to break backwards compat. But even if they did it now it would be too late and they'd just end up with a worse Rust or Zig.
The biggest problem with C++ is that while everyone agrees there is a great language hiding in it, everyone also has a remarkably different idea of what that great language actually is.
- Cranelift applies less optimizations in exchange for faster compilation times, because it was developed to compile WASM (wasmtime), but turns out that is good enough for Rust debug builds.
- Cranelift does not support the wide range of platforms (AFAIK just X86_64 and some ARM targets)
Hilariously, they broke this compatibility. std::auto_ptr was an abomination, but removing it from the language was needless and undermined the long term stability that differentiates C++ from upstarts.
The language itself does not change much, but the std does. It depends on individuals, but some people rely less on the std, some copy the old code that they still need.
> Are there cases where packages you may use fall behind the language?
Using third party packages is quite problematic yes. I don't recommend using them too much personally, unless you want to make more work for yourself.
Pinning your build chain and tooling to specific commits helps with stability but also traps you with old bugs or missing features. Chasing upstream fixes is a chore if you miss a release window and suddenly some depended package won't even compiile anymore.
I stopped updating the compiler at 0.14 for three projects. Getting the correct toolchain is part of my (incremental) build process. I don't use any external Zig packages.
I think one of the more PITA changes necessary to get these projects to 0.15 is removing `usingnamespace`, which I've used to implement a kind of mixin. The projects are all a few thousand LOC and it shouldn't be that much trouble, but enough trouble that none of what I gain from upgrading currently justify doing it. I think that's fine.
Mitchell Hashimoto (developer of Ghostty) talks about Zig a lot. Ghostty is written in it, and he seems to love it. The churn doesn't seem to bother him at all.
I recently tried to learn it and found it frustrating. A lot of docs are for 0.15 but the latest is (or was) 0.16 which changed a lot of std so none of the existing write ups were valid anymore. I plan to revisit once it gets more stable because I do like it when I get it to work.
Bun uses JSC (JavaScriptCore) instead of V8. From what I understand, whereas Node/V8 has a higher tier 4 "top speed", JSC is more optimized for memory and is faster to tier up early/less overhead. Good for serverless. Great for agents -> Anthropic purchase.
> Good for serverless. Great for agents -> Anthropic purchase.
Surely nobody would use javascript for either yea? The weaknesses of the language are amplified in constrained environments: low certainty, high memory pressure, high startup costs.
I think Bun helps with the memory pressure, granted this is relative to V8. I'd pushback on the certainty with the reality that TS provides a significant drop in entropy while benefiting from what is a sweet spot between massive corpus size and low barrier for typical problem/use-case complexity. You'll never have the fastest product with JS, but you will always have good speed to market and be able to move quickly.
The actual JS code is in the same ballpark as nodejs. They get fast by specializing to each platform's fastest APIs instead of using generic ones, reimplementing JS libraries in Zig (for example npm or jest) and using faster libraries (for example they use the oniguruma regex engine). Also you don't need an extra transpiling step when using TypeScript.
A 30K-line PR for type resolution sounds scary but this is exactly what pre-1.0 means. Rust went through multiple rounds of similar foundational rework before stabilization, remember the old sigil-based pointer syntax. Getting the type system formalized before committing to backwards compat is worth temporary churn. The real test is whether this new design makes future type system changes smaller and more incremental rather than requiring another 30K-line rewrite.
I am impressed by the achievements of the Zig team. I use the ghostty terminal emulator regularly -- it is built in Zig and it is super stable. It is a fantastic piece of software.
This makes me feel that the underlying technology behind Zig is solid.
But I prefer Rust over Zig. The main difference is Rust chooses a "closed world" model while Zig chooses an "open world" model: in Rust, you must explicitly implement a trait while in Zig as long as the shape fits, or the `.` on a structure member exists (for whichever type you pass in), it will work (I don't use Zig so pardon hand wavy description).
This gives Zig very powerful meta programming abilities but is a pain because you don't know what kind of type "shapes" will be used in a particular piece of code. Zig is similar to C++ templates in some respects.
This has a ripple effect everywhere. Rust generated documentation is very rich and explicit about what functions a structure supports (as each trait is explicitly enrolled and implemented). In Zig the dynamic nature of the code becomes a problem with autocomplete, documentation, LSP support, ...
> But I prefer Rust over Zig. The main difference is Rust chooses a "closed world" model while Zig chooses an "open world" model: in Rust, you must explicitly implement a trait while in Zig as long as the shape fits, or the `.` on a structure member exists (for whichever type you pass in), it will work (I don't use Zig so pardon hand wavy description).
Do you happen to have a more specific example by any chance? I’d be interested in what this looks like in practice, because what you described sounds a bit like Go interfaces and from my understanding of Zig, there’s no direct equivalent to it, other than variations of fieldParentPtr.
They are referring to `anytype`, which is a comptime construct telling the compiler that the parameter can be of any type and as long as the code compiles with the given value, it's good.
It's an extremely useful thing, but unconstrained, it's essentially duck typing during compile time. People has been wanting some kind of trait/interface support to constrain it, but it's unlikely to happen.
Congratulations to the dev, a 30,000 line PR for a language compiler (and a very much non-trivial compiler) is a feat to be proud of. But a change of this magnitude is a serious bit of development and gave me pause.
I understand both of the following:
1. Language development is a tricky subject, in general, but especially for those languages looking for wide adoption or hoping for ‘generational’ (program life span being measured in multiple decades) usage in infrastructure, etc.
2) Zig is a young-ish language, not at 1.0, and explicitly evolving as of the posting of TFA
With those points as caveats, I find the casualness of the following (from the codeburg post linked on the devlog) surprising:
‘’’This branch changes the semantics of "uninstantiable" types (things like noreturn, that is, types which contain no values). I wasn't originally planning to do this here, but matching the semantics of master was pretty difficult because the existing semantics don't make much sense.’’’
I don’t know Zig’s particular strategy and terminology for language and compiler development, but I would assume the usage of ‘branch’ here implies this is not a change fully/formally adopted by the language but more a fully implemented proposal. Even if it is just a proposal for change, the large scale of the rewrite and clear implication that the author expects it to be well received strikes me as uncommon confidence. Changing the semantics of a language with any production use is nearly definitionally MAJOR, to just blithely state your PR changes semantics and proceed with no deep discussion (which could have previously happened, IDK) or serious justification or statements concerning the limited effect of those changes is not something I have experienced watching the evolution (or de-evolution) of other less ‘serious’ languages.
Is this a “this dev” thing, a Zig thing, or am just out of touch with modern language (or even larger scale development) projects?
Also, not particularly important or really significant to the overall thrust of TFA, but the author uses the phrase “modern Zig”, which given Zig’s age and seeming rate of change currently struck me as a very funny turn of phrase.
When someone's communication is casual and informal, without any context, you really can't distinguish between:
* The author is being flippant and not taking the situation seriously enough.
* The author is presuming a high-trust audience that knows that they have done all the due diligence and don't have to restate all of that.
In this case, it's a devlog (i.e. not a "marketing post") for a language that isn't at 1.0 yet. A certain amount of "if you're here, you probably have some background" is probably reasonable.
The post does link directly to the PR and the PR has a lot more context that clearly conveys the author knows what they are doing.
It is weird reading about (minor) breaking language changes sort of mentioned in passing. We're used to languages being extremely stable. But Zig isn't 1.0 yet. Andrew and friends certainly take user stability seriously, but you signed up for a certain amount of breakage if you pick the language today.
As someone who maintains a post-1.0 language, there really is a lot of value in breaking changes like this. It's good to fix things while your userbase is small. It's maddening to have to live with obvious warts in the language simply because the userbase got too big for you to feasibly fix it, even when all the users wish you could fix it too. (Witness: The broken precedence of bitwise operators in C.)
It's better for all future users to get the language as clean and solid as you can while it's still malleable.
mlugg is one of the core contributors of Zig, and is a member of the Zig foundation iirc. They've been wanting to work on dependency resolution for a while now, so I'm really glad they're cleaning this up (I've been bitten before by unclear circular dependency errors). There's not a formal language spec yet, since it's moving pretty fast, but tbh I don't see the need for a standard, since that's not one of their goals currently.
> A (fairly uncontroversial) subset of this behavior was implemented in [the changeset we are discussing]. I'll close this for now, though I'll probably end up revisiting these semantics more precisely at some point, in which case I'll open a new issue on Codeberg.
I don't know how evident this is to the casual HN reader, but to me this changeset very obviously moves Zig the language from experimental territory a large degree towards being formally specified, because it makes type resolution a Directed Acyclic Graph. Just look at how many bugs it resolved to get a feel for it. This changeset alone will make the next release of the compiler significantly more robust.
Now, I like talking about its design and development, but all that being said, Zig project does not aim for full transparency. It says right there in the README:
> Zig is Free and Open Source Software. We welcome bug reports and patches from everyone. However, keep in mind that Zig governance is BDFN (Benevolent Dictator For Now) which means that Andrew Kelley has final say on the design and implementation of everything.
It's up to you to decide whether the language and project are in trustworthy hands. I can tell you this much: we (the dev team) have a strong vision and we care deeply about the project, both to fulfill our own dreams as well as those of our esteemed users whom we serve[1]. Furthermore, as a 501(c)(3) non-profit we have no motive to enshittify.
I don't use Zig (is not a language for me), but I like to read/watch about it, when you or others talk about the language design and the reasons behind the changes.
Just thinking out loud here, perhaps behavior like this has been more normalized because of the total shitshow that C is. Which followed all these supposedly correct rules.
They literally ended the comment by asking. I don't get why you're criticizing them for providing context that they're not an expert. You're literally distracting from the comment you're telling them has useful information on it, but in a weirdly aggressive way.
How's your experience with the constantly changing language? How're your update/rewrite cycles looking like? Are there cases where packages you may use fall behind the language?
I know Bun's using zig to a degree of success, was wondering how the rest were doing.
The language and stdlib changing hasn't been a major pain point in at least a year or two. There was some upgrade a couple of years ago that took us awhile to land (I think it might have been 0.12 -> 0.13 but I could be misremembering the exact version) but it's been smooth sailing for a long time now.
These days I'd put breaking releases in the "minor nuisance" category, and when people ask what I've liked and disliked about using Zig I rarely even remember to bring it up.
[0]: https://github.com/roc-lang/roc
These larger zig projects will stick to a tagged release (which doesn't change), and upgrade to newly tagged releases, usually a few days or months after they come out. The upgrade itself takes like a week, depending on the amount of changes to be done. These projects also tend to not use other zig dependencies.
[0]: https://github.com/tigerbeetle/tigerbeetle/pulls?q=is%3Apr+a...
[1]: https://github.com/Syndica/sig/pulls?q=is%3Apr+author%3Akpro...
Have you tried rust? how does it compared to zig?
* just asking
Rust is a modern C++/OCaml
So if you enjoy C++, Rust is for you. If you enjoy C and wish it was more verbose and more modern, try Zig.
Also, my .zig-cache is currently at 173GB, which causes some issues on the small Linux ARM VPS I test with.
As for upgrades. I upgraded lightpanda to 0.14 then 0.15 and it was fine. I think for lightpanda, the 0.16 changes might not be too bad, with the only potential issue coming from our use of libcurl and our small websocket server (for CDP connections). Those layers are relatively isolated / abstracted, so I'm hopeful.
As a library developer, I've given up following / tracking 0.16. For one, the change don't resonate with me, and for another, it's changing far too fast. I don't think anyone expects 0.16 support in a library right now. I've gotten PRs for my "dev" branches from a few brave souls and everyone seems happy with that arrangement.
I don't use zig. My experience has been that caches themselves are sources of bugs (not talking about zig only, but in general). Clearing all relevant caches occasionally is useful when you're experiencing weird bugs.
Do you see any major problems when you remove your .zig-cache and start over?
I was searching around for causes and came across the following issues: https://github.com/ziglang/zig/issues/15358 which was moved to https://codeberg.org/ziglang/zig/issues/30193
The following quotes stand out
> zig's caching system is designed explicitly so that garbage collection could happen in one process simultaneously while the cache is being used by another process.
> I just ran WizTree to find out why my disk was full, and the zig cache for one project alone was like 140 GB.
> not only the .zig-cache directory in my projects, but the global zig cache directory which is caching various dependencies: I'm finding each week I have to clear both caches to prevent run-away disk space
Like what's going on? This doesn't seem normal at all. I also read somewhere that zig stores every version of your binary as well? Can you shed some light on why it works like this in zigland?
There is still this disconnection on how languages under ISO process work in the industry.
This puts much more work on the compiler development side, but it's a great boon for the ecosystem.
To be fair, zig is pre 1.0, but Zig is also already 8 years old. Rust turned 1.0 at ~ 5 years, I think.
- Cranelift applies less optimizations in exchange for faster compilation times, because it was developed to compile WASM (wasmtime), but turns out that is good enough for Rust debug builds.
- Cranelift does not support the wide range of platforms (AFAIK just X86_64 and some ARM targets)
Just a degree of success?
> Are there cases where packages you may use fall behind the language?
Using third party packages is quite problematic yes. I don't recommend using them too much personally, unless you want to make more work for yourself.
I think one of the more PITA changes necessary to get these projects to 0.15 is removing `usingnamespace`, which I've used to implement a kind of mixin. The projects are all a few thousand LOC and it shouldn't be that much trouble, but enough trouble that none of what I gain from upgrading currently justify doing it. I think that's fine.
I asked him about in a thread a while back: https://news.ycombinator.com/item?id=47206009#47209313
The makers of TigerBeatle also rave about how good Zig is.
Color me extremely sceptical. Surely if you could make javascript fast google would have tried a decade ago....
Surely nobody would use javascript for either yea? The weaknesses of the language are amplified in constrained environments: low certainty, high memory pressure, high startup costs.
It's probably the most popular language for serverless.
When people go AWS, Azure, GCP,... other languages take the reigns.
This makes me feel that the underlying technology behind Zig is solid.
But I prefer Rust over Zig. The main difference is Rust chooses a "closed world" model while Zig chooses an "open world" model: in Rust, you must explicitly implement a trait while in Zig as long as the shape fits, or the `.` on a structure member exists (for whichever type you pass in), it will work (I don't use Zig so pardon hand wavy description).
This gives Zig very powerful meta programming abilities but is a pain because you don't know what kind of type "shapes" will be used in a particular piece of code. Zig is similar to C++ templates in some respects.
This has a ripple effect everywhere. Rust generated documentation is very rich and explicit about what functions a structure supports (as each trait is explicitly enrolled and implemented). In Zig the dynamic nature of the code becomes a problem with autocomplete, documentation, LSP support, ...
Do you happen to have a more specific example by any chance? I’d be interested in what this looks like in practice, because what you described sounds a bit like Go interfaces and from my understanding of Zig, there’s no direct equivalent to it, other than variations of fieldParentPtr.
It's an extremely useful thing, but unconstrained, it's essentially duck typing during compile time. People has been wanting some kind of trait/interface support to constrain it, but it's unlikely to happen.
I understand both of the following:
1. Language development is a tricky subject, in general, but especially for those languages looking for wide adoption or hoping for ‘generational’ (program life span being measured in multiple decades) usage in infrastructure, etc.
2) Zig is a young-ish language, not at 1.0, and explicitly evolving as of the posting of TFA
With those points as caveats, I find the casualness of the following (from the codeburg post linked on the devlog) surprising:
‘’’This branch changes the semantics of "uninstantiable" types (things like noreturn, that is, types which contain no values). I wasn't originally planning to do this here, but matching the semantics of master was pretty difficult because the existing semantics don't make much sense.’’’
I don’t know Zig’s particular strategy and terminology for language and compiler development, but I would assume the usage of ‘branch’ here implies this is not a change fully/formally adopted by the language but more a fully implemented proposal. Even if it is just a proposal for change, the large scale of the rewrite and clear implication that the author expects it to be well received strikes me as uncommon confidence. Changing the semantics of a language with any production use is nearly definitionally MAJOR, to just blithely state your PR changes semantics and proceed with no deep discussion (which could have previously happened, IDK) or serious justification or statements concerning the limited effect of those changes is not something I have experienced watching the evolution (or de-evolution) of other less ‘serious’ languages.
Is this a “this dev” thing, a Zig thing, or am just out of touch with modern language (or even larger scale development) projects?
Also, not particularly important or really significant to the overall thrust of TFA, but the author uses the phrase “modern Zig”, which given Zig’s age and seeming rate of change currently struck me as a very funny turn of phrase.
* The author is being flippant and not taking the situation seriously enough.
* The author is presuming a high-trust audience that knows that they have done all the due diligence and don't have to restate all of that.
In this case, it's a devlog (i.e. not a "marketing post") for a language that isn't at 1.0 yet. A certain amount of "if you're here, you probably have some background" is probably reasonable.
The post does link directly to the PR and the PR has a lot more context that clearly conveys the author knows what they are doing.
It is weird reading about (minor) breaking language changes sort of mentioned in passing. We're used to languages being extremely stable. But Zig isn't 1.0 yet. Andrew and friends certainly take user stability seriously, but you signed up for a certain amount of breakage if you pick the language today.
As someone who maintains a post-1.0 language, there really is a lot of value in breaking changes like this. It's good to fix things while your userbase is small. It's maddening to have to live with obvious warts in the language simply because the userbase got too big for you to feasibly fix it, even when all the users wish you could fix it too. (Witness: The broken precedence of bitwise operators in C.)
It's better for all future users to get the language as clean and solid as you can while it's still malleable.
This was proposed, discussed, and accepted here: https://github.com/ziglang/zig/issues/3257
Later, Matthew Lugg made a follow-up proposal, which was discussed both publicly and in ZSF core team meetings. https://github.com/ziglang/zig/issues/15909
He writes:
> A (fairly uncontroversial) subset of this behavior was implemented in [the changeset we are discussing]. I'll close this for now, though I'll probably end up revisiting these semantics more precisely at some point, in which case I'll open a new issue on Codeberg.
I don't know how evident this is to the casual HN reader, but to me this changeset very obviously moves Zig the language from experimental territory a large degree towards being formally specified, because it makes type resolution a Directed Acyclic Graph. Just look at how many bugs it resolved to get a feel for it. This changeset alone will make the next release of the compiler significantly more robust.
Now, I like talking about its design and development, but all that being said, Zig project does not aim for full transparency. It says right there in the README:
> Zig is Free and Open Source Software. We welcome bug reports and patches from everyone. However, keep in mind that Zig governance is BDFN (Benevolent Dictator For Now) which means that Andrew Kelley has final say on the design and implementation of everything.
It's up to you to decide whether the language and project are in trustworthy hands. I can tell you this much: we (the dev team) have a strong vision and we care deeply about the project, both to fulfill our own dreams as well as those of our esteemed users whom we serve[1]. Furthermore, as a 501(c)(3) non-profit we have no motive to enshittify.
[1]: https://ziglang.org/documentation/master/#Zen
It's been incredible working with Matthew. I hope I can have the pleasure to continue to call him my colleague for many years to come.
Thanks for your and the Zig team work.
Great to hear; I look forward to reading the language spec one day.
Indeed you don't ... perhaps you should have asked.
> I would assume
Generally a bad idea.
> which could have previously happened, IDK
Indeed you don't. Perhaps you should have asked.
Check the response from the language BDFN, Andrew Kelley.