Also worth noting that "translated from C++" Rust is totally fine as a starting point. You can incrementally make it more idiomatic later once the C++ side is retired. The Rust compiler will still catch whole classes of memory bugs even if the code reads a bit weird. That's the whole point.
This is a HUUUGE reason code written in rust tended to be so much better than the original (which was probably written in c++).
Human expertise is the single most important factor and is more important than language.
Copy pasting from one language to another is way worse than complete rewrite with actual idiomatic and useful code.
Best option after proper rewrite is binding. And copy-paste with LLM comes way below these options imo.
If you look at real world, basically all value is created by boring and hated languages. Because people spent so much effort on making those languages useful, and other people spent so much effort learning and using those languages.
Don’t think anyone would prefer to work in a rust codebase that an LLM copy-pasted from c++, compared to working on a c++ codebase written by actual people that they can interact with.
But translating with automated tools is a much faster experiment.
Sometimes (not always), rewriting from scratch ends up in a big loss of time and resources and never replaces the old version.
This is the way. Coding assistants are also really great at porting from one language to the other, especially if you have existing tests.
I had a broken, one-off Perl script, a relic from the days when everyone thought Drupal was the future (long time ago). It was originally designed to migrate a site from an unmaintained internal CMS to Drupal. The CMS was ancient and it only ran in a VM for "look what we built a million years ago" purposes (I even had written permission from my ex-employer to keep that thing).
Just for a laugh, I fed this mess of undeclared dependencies and missing logic into Claude and told it to port the whole thing to Rust. It spent 80 minutes researching Drupal and coding, then "one-shotted" a functional import tool. Not only did it mirror the original design and module structure, but it also implemented several custom plugins based on hints it found in my old code comments.
It burned through a mountain of tokens, but 10/10 - would generate tens of thousands of lines of useless code again.
The Epilogue: That site has since been ported to WordPress, then ProcessWire, then rebuilt as a Node.js app. Word on the street is that some poor souls are currently trying to port it to Next.js.
Me too! A couple days ago I gave claude the JMAP spec and asked it to write a JMAP based webmail client in rust from scratch. And it did! It burned a mountain of tokens, and its got more than a few bugs. But now I've got my very own email client, powered by the stalwart email server. The rust code compiles into a 2mb wasm bundle that does everything client side. Its somehow insanely fast. Honestly, its the fastest email client I've ever used by far. Everything feels instant.
I don't need my own email client, but I have one now. So unnecessary, and yet strangely fun.
Its quite a testament to JMAP that you can feed the RFC into claude and get a janky client out. I wonder what semi-useless junk I should get it to make next? I bet it wouldn't do as good a job with IMAP, but maybe if I let it use an IMAP library someone's already made? Might be worth a try!
Claude’s toy email client gets closer to the speed limit than Gmail does. Why is Gmail so slow? I have no idea.
RE: Claude Code, no I haven't used it, but I did do the Anthropic interview problem, beating all of Anthropic's reported Claude scores even with custom harnesses etc.
It's not a dunk that agents can't produce "as fast as can be" code; their code is usually still reasonably fast; it's just often 2-10x slower than can be.
Defect free. Immaculate types. Safe. Ergonomic. Beautiful to read.
AI is going to be writing a lot of Rust.
The final arguments of "rust is hard to write" are going to quiet down. This makes it even more accessible.
> Defect free.
I am an upstream developer on the Rust Project (lang, library, cargo, others), and obviously a big fan of Rust. This kind of advocacy doesn't help us, and in fact makes our jobs harder, because for some people this kind of advocacy is their main experience of people they assume are representative of Rust. Please take it down a notch.
I think Rust is the best available language for many kinds of problems. Not yet all, but we're always improving it to try to work for more people. It gets better over time. I'd certainly never call it, or almost any other software, "defect free".
And I'd never call it "the final language"; we're building it to last the test of time, and we hope things like the edition system mean that the successor to Rust is a future version of Rust, but things can always change, and we're not the only source of great ideas.
If you genuinely care about Rust, please adjust your advocacy of Rust to avoid hurting Rust and generating negative perceptions of Rust.
For a taste: I wish we didn’t need lifetime annotations, somehow. I wish rust had first class support for self borrows, possibly via explicit syntax indicating that a variable is borrowed, and thus pinned. Unpin breaks my brain, and I wish there were ways to do pin projections without getting a PhD first. I wish for async streams. I wish async executors were in std, and didn’t take so long to compile. I could go on and on.
I feel like there’s an even simpler & more beautiful language hiding inside rust. I can’t quite see it. But I really hope someone else can bring it into the world some day.
Oh my, there's a new language called Rust? Didn't they know there already is one? The old one is so popular that I can't imagine the nicely readable one to gain any traction whatsoever (even if the old one is an assault on the senses).
I honestly can't tell if this is a humorous attack or not.
Poe's law is validated once again.
It's not the best tool for the job for a lot of things, but if the LLMs make writing it as fast as anything else - whelp, I can't see any reason not to do it in Rust.
If you get any language outputs "for free", Rust is the way to go.
I've been using Claude to go ridiculously fast in Rust recently. In the pre-LLM years I wrote a lot of Rust, but it definitely was a slow to author language. Claude helps me produce it as fast as I can think. I spend most of my time reviewing the code and making small fixes and refactors. It's great.
I used to think that I would never write C code again, but when I decided recently to build something that would run on ESP32 chips, I realized there wasn't any good reason for me to use Rust yet. ESP-IDF is built on C and I can write C code just fine. C compiles quickly, it's a very simple language on the surface, and as long as you minimize the use of dynamic memory allocation and other pitfalls, it's reliable.
My biggest problem with rust right now is enormous target/ dirs.
We're working on that and it should get better soonish. We're working on shared caches, as well as pruning of old cached builds of dependencies that are unlikely to be reused in a future build.
Claude is an Anthropic offering.
It's not, nor is it well informed. People are currently developing languages specifically for use by LLMs.
> It's not the best tool for the job for a lot of things
Then how could it possibly be the final language?
> if the LLMs make writing it as fast as anything else - whelp, I can't see any reason not to do it in Rust
This has nothing to do with the claim that it's the final language.
As AI makes human-readable syntax less relevant, the Erlang/Elixir BEAM virtual machine is an ideal compilation target because its "let it crash" isolated process model provides system-level fault tolerance against AI logic errors, arguably more valuable than Rust’s strict memory safety.
The native Actor Model simplifies massive concurrency by eliminating shared state and the complex thread management. BEAM's hot code swapping capability also enables a continuous deployment where an AI can dynamically rewrite and inject optimized functions directly into live applications with zero downtime.
Imagine a future where an LLM is constantly monitoring server performance, profiling execution times, and dynamically rewriting sub-optimal functions in real-time. With Rust, every optimization requires a recompile and a deployment cycle that interrupts the system.
Finally, Erlang's functional immutability makes deterministic AI reasoning easier, while its built-in clustering replaces complex external infrastructure, making it a resilient platform suited for automated iteration.
And fyi, jmap is just a protocol for doing email over json & http. It’s not that hard to roll your own. Especially in a web browser.
This is the biggest bottleneck at this point. I'm looking forward to RAM production increasing, and getting to a point where every high-end PC (workstation & gaming) has a dedicated NPU next to the GPU. You'll be able to do this kind of stuff as much as you want, using any local model you want. Run a ralph loop continuously for 72 hours? No problem.
But let's be honest to ourselves, the sort of useless code the GP meant will never ever be used for any of that. The code will never leave their personal storage. In that sense it's about as valuable for the society at large as the combined exabytes of GenAI smut that people have been filling their drives with by running their 4090s 24/7.
No that’s a stretch, but firing up a AAA game.
How long time do we have to wait before these people get bored? Or might they actually find what they generate useful and it doesn't all go straight to /dev/null, since seemingly it seems to gain usage, not drop in usage?
Drupal is the future. I never really used it properly, but if you fully buy into Drupal, it can do most everything without programming, and you can write plugins (extensions? whatever they're called...) to do the few things that do need programming.
> The Epilogue: That site has since been ported to WordPress, then ProcessWire, then rebuilt as a Node.js app. Word on the street is that some poor souls are currently trying to port it to Next.js.
This is the problem! Fickle halfwits mindlessly buying into whatever "next big thing" is currently fashionable. They shoulda just learned Drupal...
Wordpress loves to shove php objects into the database (been a good long while since I used it, don't remember the mechanism, it'd be the equivalent of `pickle` in python, only readable by php).
Not sure if they've improved it since I last dealt with it about 15 years ago, but at the time there was no way to have a full separated staging and production environment, lots of the data stored in the database that way had hardcoded domain names built into it. We needed to have a staging and production kind of set-up, so we ended up having to write a PHP script that would dump the staging database, fix every reference, and push it to production. Fun times.
No idea what's used in wordpress, but back in D6 and before, it was common to see it when it would store multiple values for an instance.
Pardon me, and, yes, I know we're on HN, but I guess you're... rich? I imagine a single run like this probably burns through tens or hundreds of dollars. For a joke, basically.
I guess I understand why some people really like AI :-)
All of them are moving into the direction of "less human involved and agents do more", while what I really want is better tooling for me to work closer with AI and be better at reviewing/steering it, and be more involved. I don't want "Fire one prompt and get somewhat working code", I want a UX tailored for long sessions with back and forth, letting me leverage my skills, rather than agents trying to emulate what I already can do myself.
It was said a long time ago about computing in general, but more fitting than ever, "Augmenting the human intellect" is what we should aim for, not replacing the human intellect. IA ("Intelligence amplification") rather than AI.
But I'm guessing the target market for such tools would be much smaller, basically would require you to already understand software development, and know what you want, while all AI companies seem to target non-developers wanting to build software now. It's no-code all over again essentially.
Same thing.
(or generally: “Is the cocaine cartel comparison fair or unfair?”)
Is that what you mean by IA?
For example, I type "for" and my editor guesses I want to iterate over the list that is the second argument of the function for which I am currently building the body. So it offers to complete the rest of the loop condition for me. Not only did it anticipate that I am writing a for loop. It figures out what I want to iterate over, and perhaps even that I want to enumerate the iteration so I have the index and the value. Imagine if I had written a comment to explain my intent for the function before I started writing the function body. How much better could it augment my intellect?
I'm guessing the direction I'd prefer, would be tooling built to accept and be driven by humans, but allowed to be extended/corrected by AI, or something like that, maybe.
Maybe a slight contradiction, and very wish-washy/hand-wavey, but I haven't personally quite figured out what I think would be best yet either, what the right level actually is, so probably the best I could say right now :) Sorry!
>Imagine if I had written a comment to explain my intent for the function before I started writing the function body.
This in particular is not dissimilar from opening a chat with a model and giving it a prompt as usual but then adding at the end:
Begin your response below:
{ func> Imagine if I had written a comment to explain my intent for the function before I started writing the function body.
The loon programming language (a Lisp) has "semantic functions", where the body is just the doc comment.
I want less ambitious LLM powered tools than what's being offered. For example, I'd love a tool that can analyse whether comments have been kept up to date with the code they refer to. I don't want it to change anything I just want it to tell me of any problems. A linter basically. I imagine LLMs would be a good foundation for this.
One problem I've noticed is that both claude models and gpt-codex variants make absolutely deranged tool calls (like `cat <<'EOF' >> foo...EOF` pattern to create a file, or sed to read a couple lines), so it's sometimes hard to see what is it even trying to do.
I'm sure it can. I'd still like a single use tool though.
But that's just my taste. I'm very simple. I don't even use an IDE.
edit: to expand on what I mean. I would love it if there was a tool that has conquered the problem and doesn't require me to chat with it. I'm all for LLMs helping and facilitating the coding process, but I'm so far disappointed in the experience. I want something more like the traditional process but using LLMs to solve problems that would be otherwise difficult to solve computationally.
This is because, regardless of the current state of things, the endgame which will justify all the upfront investment is autonomous, self-improving, self-maintaining systems.
"Bicycle for the mind", as always when it involves Jobs, sounds more fitting for the masses though, so thanks for sharing that :)
Though if apocalypse happens and all of our built tech goes away, we are in for a serious survival issu.
given that we've also lost the faculty to look at the past with anything other than contempt most people wouldn't even know what they miss. The little problem with losing the 'general cognition' department, just like broad social or cultural decline is that you lose the ability to even judge what you're losing, because the thing you just lost was doing the judging
(1) It captures the ideal so well
(2) The bitter irony of how thoroughly pre-OS X Macintosh computers failed to live up to it
I feel like there's a similar dichotomy in LLM tools now
their valuations are replaced on getting rid of you entirely, along with everyone else
the "humans can use it to increase their productivity" is an interim step
I decided to create a Claude skill called "teach". When I enable it, Claude never writes any code. It just gives me hints - progressively more detailed if I am stuck. Then it reviews what I write.
I am finding it very satisfying to work this way - Rust in particular is a language where there's little space to "wing it". Most language features are interlaced with each other and having an LLM supporting me helps a lot. "Let's not declare a type for this right now, we would have to deal with several lifetime issues, let's add a note to the plan and revisit this later".
This link also has a comparison to Skills further down.
https://code.claude.com/docs/en/output-styles#built-in-outpu...
I used Claude to rewrite it in golang and extend its features. Now I have tests, automatic AIA chain walking, support for all the DER and JKS formats, and it’s fast. My bash script could spend a few minutes churning through a folder with certs and keys, my golang version does a few thousand in a second.
So I basically built a limited version of OpenSSL with better ergonomics and a lot of magic under the hood because you don’t have to specify input formats at all. I wasn’t constrained by things like backwards compatibility and interface stability, which let me make something much nicer to use.
I even was able to build a wasm version so it can run in the browser. All this from someone that is not a great coder. Don’t worry, I’m explicitly not rolling my own crypto.
The industry hasn't come up with a simple meme-format term to explain this workflow pattern yet, so people aren't excited about it. But don't worry, we'll surely have a bullshit term for it soon, and managers everywhere will be excited. In the meantime, we can just continue doing work with these new tools.
Don’t do that! On a two-day-old term?!
No wonder we’re called gatekeepers.
It's vibe engineering
Operative word being “some”. The issue is that too many aren’t doing it that way.
> You dont just go “build thing”
Tell that to the overwhelming majority of posters discussing vibe coding, including on HN.
As long as they get paid for it (or have fun, if it's a personal project), they couldn't care less about that. Tomorrow's problems are overrated.
The difference now is they can get much further along.
Thinking people who disagree with you hate you or hate the thing you like is a recipe for disaster. It's much better to not love or hate things like this, and instead just observe and come to useful, outcome-based conclusions.
There's a huge distinction between Vibe Coding, and actual software engineers using AI tooling effectively. I vibe code for fun sometimes too, nothing wrong with it, helps me figure out how the model behaves in some instances, and to push the limits of what I understand.
There's other things too though: my ADD and my impostor syndrome don't matter to Claude, Claude just takes it all in, so as I keep brain dumping, it keeps chugging along. I don't have to worry a bout "can I really do this?" it just does it and I can focus on "what can I do to make it better" essentially.
For me it's beyond "porn coding" its basically fulfilling my vision that's been locked away for years but I've had no time to sit down and do it fully. I can tell Claude to do something, my kid comes up and asks me to go draw with them and I can actually just walk away and look at the output and refine.
I absolutely hate how "slop" has lost its meaning.
"AI slop" was supposed to mean poor-quality content that's obviously AI-generated. But the anti-AI crowd has co-opted it to mean any AI-generated content, regardless of quality. EDIT: Or even the quantity of AI. Expedition 33 had a ton of critical acclaim and ended up winning tons of awards, yet once it was discovered that AI was used to generate some placeholder art, of which NONE of it was actually used in the final product, some people started labeling the game as AI slop. It's utterly ridiculous.
So now, we can't have conversations about AI slop without starting off with making sure everyone is on the same page on what the term even means.
EDIT: "Vibe coding" is suffering a similar fate. If I use AI to write some code, and I examine the code to make sure it doesn't have any obvious bugs or security issues, is that still vibe coding?
> We’ve verified that every AST produced by the Rust parser is identical to the C++ one, and all bytecode generated by the Rust compiler is identical to the C++ compiler’s output.
Is this a conventional goal? It seems like quite an achievement.
Porting a project from PHP7 to PHP8, you'd want the exact same SQL statements to be sent to the server for your test suite, or at least be able to explain the differences. Porting AngularJS to Vue, you'd want the same backend requests, etc..
I’ve been throwing codex at them and now they’ve all been rewritten in Go - cut down to about 10mb per process.
In my coding agent std::slop I've optimized for this workflow https://github.com/hsaliak/std_slop/blob/main/docs/mail_mode... basically the idea is that you are the 'maintainer' and you get bisect safe, git patches that you review (or ask a code reviewer skill or another agent to review). Any change re-rolls the whole stack. Git already supports such a flow and I added it to the agent. A simple markdown skill does not work because it 'forgets'. A 'github' based PR flow felt too externally dependent. This workflow is enforced by a 'patcher' skill, and once that's active, tools do not work unless they follow the enforced flow.
I think a lot of people are going to feel comfortable using agents this way rather than going full blast. I do all my development this way.
Would be curious to see more about how you save tokens with lua too.
Do you blog?
- A bit more on mail mode https://x.com/hsaliak/status/2020022329154420830
- on the Lua integration https://x.com/hsaliak/status/2022911468262350976 (I've since disabled the recursion, not every code file is long and it seems simpler to not do it), but the rest of it is still there
- hotwords for skill activation https://x.com/hsaliak/status/2024322170353037788
Also /review and /feedback. /feedback (the non code version) opens up the LLM's last response in an editor so you can give line by line comments. Inspired by "not top posting" from mailing lists.
All my vibe coded projects are human directed, unless explicitly stated otherwise
No, they are quite terrible at doing that.
They may (I guess?) produce code that compiles, but they will, almost certainly not produce the appropriate combination of idioms and custom abstractions that may the code "at home" in the target language.
PS - Please fix your blockquote... HN ignores single linebreaks, so you have to either using pairs of them, or possibly go with italicization of the quoted text.
And you might say that this is a hypothetical problem, one that is not practically occurring. Well, we had a similar problem like this in the recent past, that LLMs are close to _making actual_. When it comes to software patents, they were considered a _hypothetical_ problem (i.e. nobody is going to bother suing you unless you were so big that violating a patent was a near certainty). We were instructed (at pretty much all jobs), to never read patents, so that we cannot incriminate ourselves in the discovery process.
That is going to change soon (within a year). I have friend, whom I won't name, who is working on a project, using LLMs, to discover whether software (open source and proprietary) is likely to be violating a software patent from a patent database. And it is designed to be used, not by programmers, but by law firms, patent attorneys, etc. Even though it is not marketed this way, it is essentially a target acquisition system for use by patent trolls. It is hard for me to tell if this means that we will have to keep ignoring patents for that plausible deniability, or if this means that we will have to become hyper informed about all patents. I suppose, we can just subscribe to the patent-agent, and hope that it guides the other coding agents into avoiding the insertion of potentially infringing code.
(I also have a friend who built a system in 2020 that could translate between C++ and Python, and guarantee equivalent results, and code that looks human-written. This was a very impressive achievement, especially because of how it guarantees the equivalence (it did not require machine-learning nor GPUs, just CPUs and some classic algorithms from the 80s). The friend informs me that they are very disheartened to see that now any toddler with a credit card can mindlessly do something similar, invalidating around a decade of unpublished research. They tell me that it will remain unpublished, and if they could go back in time, they would spend that decade extracting as much surplus from society as possible, by hook or by crook (apparently they had the means and the opportunity, but lacked the motive); we should all learn from my friend's mistake. The only people who succeed are, sadly, perversely, those who brazenly and shamelessly steal -- and make no mistake, the AI companies are built on theft. When millionaires do it, they become billionaires -- when Aaron Swartz does it, he is sentenced to federal prison. I'm not quite a pessimist yet, but it really is saddening to watch my friend go from a passionate optimist to a cold nihilist.).
If there was value (the guarantees) to this tech he buried a bunch of time in, he should be wrapping a natural language prompt around it and selling it.
Not even the top providers are giving any sort of tangible safety or reliability guarantees in the enterprise…
I don't know if it's a good fit. Not because they're writing a browser engine in Rust (good), but because Ladybird praises CPP/Swift currently and have no idea what the contributor's stance is.
At least contributing will be a lot nicer from my end, because my PR's to Ladybird have been bad due to having no CPP experience. I had no idea what I was doing.
Yeah that is the thing I struggle with. I am really happy for people falling in love with Rust. It is a amazing language when used for the right use case.
The problem is that had my Rust adventures a few years ago and I am over the hype cycle and able to see both the advantages and disadvantages. Plus being generally older and hopefully wiser I don't tie my identity towards any specific programming language that much.
So sometimes when some Junior dev discovers Rust and they get really obnoxious with their evangelicalism it can be very off putting. Really not sure how to solve it. It is good when people get excited about a language. It just can be very annoying for everyone else sometimes.
This rings very true, and I've actually disadvantaged myself somewhat here. I was involved in projects that made very dubious decisions to rewrite large systems in Rust. This caused me to actively stay away from the language, and stick to C++, investing lots of time in overcoming its shortcomings.
Now years later, I started with Rust in a new project. And I must say, I like the language, I really like the tools, and I like the ecosystem. On some dimension I wish I would have done this sooner (but on the other hand, I think I have a better justification of "why Rust" now).
1. build / compile times can be atrocious
2. crates.io inherits the npm philosophy, which means fairly unmoderated space of third party deps and because the Rust stdlib doesn't have a lot in it, extensive third party crate (lib) usage is strong in Rust. As a result most Rust projects have rather sprawling dependency trees, often with duplicated functionality (multiple Base64, rand, sha256, etc crates). I personally have a problem with this (auditability, accountability, security, complexity etc). Others don't.
3. Despite being nominally runtime agnostic, Rust async basically is tokio and it's almost impossible to use another runtime once you factor in third party deps. In many ways Rust is the language that tokio ate. In fact even if you opt out of async entirely, you often end up with tokio as a dependency simply because the community just seems to expect it.
4. Despite advertising itself as a "systems" language, some basic systems programming facilities I expect from my C++ background are still fundamentally not there. In particular, per-container/struct pluggable allocators still isn't a thing and the feature to add it (allocator-api) has sat unmerged in nightly for almost ten years at this point and it doesn't look good for it landing any time soon.
5. If you're working in the embedded space, there's still plenty of devices that will not have a workable Rust toolchain option yet.
I still choose it for new projects instead of its competitors C++ or Zig. But I think it's important to recognize there are compromises like any other tool.
As much as people might insist otherwise, there will in fact come a day when there are "multiple Rusts" by which I mean multiple styles and ways of doing things -- just like C++. For myself, for example... if it were my repository and my team and my hiring, and I was starting from scratch... I'd be extremely careful about third party crate adoption and have an extremely minimalistic approach there. And I don't use tokio. Though my paying jobs do.
And experience doesn't equal correct decision making. People just get traumatized in different ways.
Problem with community is it has experts and groupies mixed in. Ideally experts can talk somewhere and groupies can go somewhere else and talk about funding RSF etc. but now is unnecessary. Expert is available on demand via chatbot.
Personally I think most programming languages have really ... huge problems. And the languages that are more fun to use, ruby or python, are slow. I wonder if we could have a great, effective, elegant language that is also slow. All that try end up with e. g. with a C++ like language.
Rust, although annoying at a micro scale, does at least enforce some structure on your code, although like Kling I miss OO.
AI has made Rust approachable to a new audience of programmers who didn't want to dedicate their life to learning the ins and outs of the language. Especially for C++ developers who already learned the ins and outs of a hyper complex programming language and don't want to go through that a second time.
Before AI, writing Rust was frustrating experience that involved spending 90% of your time reading documentation and grumbling that "I could do this in 5 minutes in C++"
Now I can write Rust in a way that makes sense to my C++ addled brain and let the AI do the important job of turning it into an idiomatic Rust program that compiles.
Not anymore.
Next month it will be yet-another-language.
Eventually they come full circle and settle for either C or C++.
As a browser, Ladybird usefulness is currently quite limited for obvious reasons. This is not meant to dismiss its achievements, nor to overlook the fact that building a truly useful browser for everyday users is something few open source teams can accomplish without the backing of a billion dollar company. Still, in its present state, its practical utility remains limited.
Ladybird will have to deliver eventually - on this part I think many people agree with.
A release (?)
Not just volatility but also flip-flopping. Rust was explicitly a contender when they decided to go with Swift 18 months ago, and they've already done a 180 on it despite the language being more or less the same as it was.
For the Ladybird project, now is the best time to be making a big decision like this, and it's commendable that the project lead was honest to recognize when an earlier attempt was not working, to be able to re-think and come to a better decision. I'm no fan of Rust, but for this project I think most of us would agree it's a better language than Swift for their purpose.
I've seen another team doing something similar, they went through endless rewrite cycles of a major package but never shipped, and eventually the project was axed when they proposed to do it all over again, but this time even better.
Doesn't sound like it's some Fish-style, full migration to Rust of everything. Seems like they are just moving a couple parts over for evaluation, and then, going forward, making it an official project language that folks are free to use. They note that basically every browser already does that, so this isn't a huge shakeup.
> ... the entire port took about two weeks.
So he was ~halfway in when he made the Swift announcement.
if it works it works i guess, but it seems mad to me on the surface
the relevant bit here is that he's porting from a language in which he has plenty of experience into another one in which he doesn't, in a large project
that in itself sounds like putting a lot of faith in LLMs but maybe there are factors not mentioned here, which is why i said "on the surface"
Also, as others have pointed out, "someone with no experience" simply isn't true.
you're banking in the LLMs quite strongly when you do that, which may just work but i would be very worried about myself if i were in his boots
He did write it.
> you're banking in the LLMs quite strongly when you do that, which may just work but i would be very worried about myself if i were in his boots
I too would worry if it were you doing it.
I mean, they seem mostly to be against anything that isn't C++'s peculiar brand of Object Oriented Programming?
(also against women and immigrants, but that's a different story)
The Jakt -> Swift -> Rust pivots look like the same thing on a different level. The initial change to Swift was surely motivated by potential industry support gain (i believe it was a dubious choice from purely engineering standpoint).
It's awe-inspiring to see how a person can carve a job for himself, leverage hobbyists'/hackers' interest and contributions, attract industry attention and sponsors all while doing the thing he likes (assuming, browsers are his thing) in a controlling position.
Can't fully rationalize the feeling, but all of this makes me slightly wary. Doesn't make it less cool to observe from a side, though.
You get to good at schmoozing the compiler you start to create actual logical bugs faster.
LLM and rust rewrite together. And it does work so hopefully they get more attention and build it so I have an alternative browser to use
Wary of what?
Long read on the topic (quite funny, covers Cluely): https://harpers.org/archive/2026/03/childs-play-sam-kriss-ai...
This doesn't mean that being agentic cannot be cultivated by regular people.
In 2026, yes, agency matters more than skill/wisdom/intelligence to get VC funds. But what's the point of agency alone if you are leading such a life?
What gives me hope is that in 2026, skillful people can delegate a lot of their work to LLMs, which gives them time to learn the "agentic" part which is basically marketing and talking with people.
(just thinking out loud)
We’re at the point where a solid test suite and a high-quality agent can achieve impressive results in the hands of a competent coder. Yes, it will still screw up, needs careful human review and steering, etc, but there is a tangible productivity improvement. I don’t think it makes sense putting numbers on it, but for many tasks, it looks like there’s a tangible benefit.
Correct me if I’m wrong since I don’t know these two languages, but like some other languages, doing things the idiomatic way could be dramatically different. Is “cleanup” doing a lot of heavy lifting here? Could that also mean another complete rewrite from scratch?
A startup switching languages after years of development is usually a big red flag. “We are rewriting it in X” posts always preceded “We are shutting down”. I wish them luck though!
Out of all the languages rust takes inspiration from, id rank C++ at the top of the list.
OOP, weakly-typed templates, and mutable aliasing create impedance mismatch in almost every C++ API.
Rust doesn't have data inheritance, and what looks like interface inheritance is merely extra requirements in a flat list of traits, so subclassing won't behave like C++ APIs expect. When you translate a class hierarchy to Rust, it needs lots of crutches which make it weird, boilerplatey, and tedious to use. There's no good recipe for OOP hierarchy in Rust, because the idioms are so different. The mismatch feels like writing an ORM.
For some C++ APIs mutability and circular references can be a pain too. Rust works well with DAG data structures and clear mostly-immutable data flow. Objects with some "parent" pointer are common in C++, but Rust sees them as potentially dangling, with shared mutable state, and requires much heavier control of them. It can be done, but it's ugly. Idiomatic Rust designs go to great lengths to avoid it unless necessary, but C++ APIs can have the extra pointers "for convenience".
There's a reason why Rust doesn't have typical GUI libraries - an arbitrary web of references between widgets and event handlers make it ugly in Rust, and that's on top of a view class inheritance.
C++ templates sit very uncomfortably between Rust's macros (duck typed) and Rust's generics (strictly typed at point of declaration).
C++ templates almost always are a mix of types they're attached to and some duck-typing in their expansion.
Rust's generics do not allow any duck typing at all. This makes translation of even a tiny bit clever C++ templates a chore. There's no specialization. No way to deal with SFINAE and such.
Rust macros have flexibility for all the syntax shenanigans (and even similarly bad errors at instantiation time), but macros can't see any types. Idiomatic Rust has very deliberate division between traits (usually much simpler and smaller in scope), macros and proc macros/derives. Splitting C++ templates like that can be a major redesign.
If you do a rewrite you essentially put everything else on halt while rewriting.
If you keep doing feature dev on the old while another "tiger team" is doing the rewrite port then these two teams are essentially in a race against each other and the port will likely never catch up. (Depending on relative velocities)
Maybe they think that they can to this LLM assisted tools in a big bang approach quickly and then continue from there without spending too much time on it.
Moving Ladybird from C++ to a safer more modern language is a real differentiator vs other browsers, and will probably pay dividends. Doing it now is better than doing it once ladybird is fully established.
One last point about rewrites: you can look at any industry disruptor as essentially a team that did a from-scratch rewrite of their competitors and won because the rewrite was better.
> I’ve been part of at least 2 successful rewrites. I think that Joel’s post is too often taken as gospel. Sometimes a rewrite is the best way forward.
I can recall recently, listening to an Oxide and Friends podcast where they spent 30 minutes dumping all over "Agile Dev", only to have a very senior, hands-on guy join from AWS and absolutely deliver the smack down. (Personally, I have no positive experiences with Agile Dev, but this guy really stunned the room into silence.) The best part: The Oxide crew immediately recognized the positive experence and backed off the give this guy the space he needed to tell and interesting story. (Hats off the Ox crew for doing that... even if I, personally, have zero love for Agile Dev.)
Rarely if ever is anything able to compete simply by being "better". As far as USPs go it's just not enough. I reckon for ladyboy the USP (if any) is going to be it being open and NOT chrome (or derivative). So "safe" "modern" language is not going to mean much to the end users.
If you ask me, Go is a better Rust. Rust is an ugly version of C++ with longer compile times and a band of zealous missionaries.
I mean the keywords mut and fn very annoying to read just get rid of them or spell the f*n thing function.
I always wonder how can one come to such a conclusion. Modern C++ has no way to enforce relationship between two objects in memory and the shared xor mutable rule, which means it can't even do the basic checks that are the foundation of Rust's safety features.
Of course, this statement is also trivially debunked by the reality of any major C++ program with complexity and attack surface of something like a browser. Modern C++ certainly didn't save Chrome from CVEs. They ban a bunch of C++ features, enforce the rule of two, and do a bunch of hardening and fuzzing on top of it and they still don't get spared from safety issues.
[1]: https://developer.chrome.com/blog/memory-safety-fonts
[2]: https://github.com/googlefonts/fontations/tree/main/skrifa
What does the memory safety even matter when hackers poison heavily used crates?
The statistics from projects that have adopted Rust and measured the effect say otherwise. See https://security.googleblog.com/2025/11/rust-in-android-move... for example.
Maybe we would see similar effects adopting Modern C++. Maybe not. The article doesn't tell us.
"mut and fn very annoying to read" like okay lol who cares? What should anyone take from your post other than that you aren't that into Rust?
The data says otherwise, three overflows and two UAFs this month in Chrome alone: https://www.cvedetails.com/vulnerability-list/vendor_id-1224...
Eh. There's a lot I like about Go. I adore its compilation speed and the focus on language simplicity. But its got plenty of drawbacks too. Default nullability is a huge mistake. And result types (zig, swift, rust) are way better than go's error handling. Sum types in general are missing from Go, and once you start using them its so hard to go back. Go also doesn't have anywhere near as good interop with native code. Mixing C (or any other LLVM langauge) with rust is easy and feels great. You even get LTO across the language barrier.
The big thing I'm growing to dislike about rust is how many transitive dependencies a lot of projects end up pulling in. Its very easy to end up with projects that take a million years to compile & produce huge binaries. Not because they do a lot but simply because everything depends on everything, and the dependency tree takes a long time to bottom out. I don't know what the right answer is. It feels more like a cultural problem than a language / ecosystem problem. But I wish rust projects felt as lightweight and small as most C projects I've worked with. I'm doing some work with the stalwart email server at the moment (written in rust). Stalwart is a relatively new, well written email server. But it somehow pulls in 893 transitive dependencies! I'm not even joking. Compiling stalwart takes about 20 minutes, and the compilation process generates several gigabytes of intermediate build assets. What a mess.
20 minutes! What hardware is this on? I've worked on Rust projects with similar numbers of dependencies where the compile time (for a clean release build) was 2-4 minutes (on a MacBook M1 Pro)
- 99% of the ~700 crates were done compiling in about a minute or 2 - RocksDB (a C++ dependency) was 2 minutes by itself - And then it took 10 minutes (ten!) just for the final binary at the end.
That's not normal for Rust code at all. Even large ones like Servo or Rustc or Zed.
UPDATE2: turns out they have LTO enabled by default. Disabling that brings the compile time down to 7 minutes. But that's still really unexpectedly slow.
I definitely agree that it's too slow. I just don't think the cause is "too many dependencies" because I've compiled Rust codebases with twice as many dependencies in half the time!
It seems to produce a 94MB binary. So it may be partly that there are some very big dependencies. But the amount of compilation time that ends up in the top-level crate (even with LTO disabled) also makes me feel like this must be triggering a compiler bug. Either that or using far too many generics.
Not quite. It doesn't have tagged unions, which is what I expect you are thinking of, but it does have sum types.
Go doesn’t have sum types as a first class primitive.
But they're not tagged unions. I expect that is still where your confusion lies. Tagged unions and sum types are not equivalent. Tagged unions are a subset of sum types.
Sum types are a type definition defining something as A or B. Not “anything that quacks like a duck”. But concretely “one of this or one of that”. This enables different syntax, like the match expression to be used, in which you exhaustively list all the variants. The compiler doesn’t need to heap allocate enums because it knows the maximum size of a single value. The compiler and programmer can take advantage of the knowledge that there’s a closed set of values the type can hold. It’s not an open type class.
Result and Option are quite beautiful as sum types. But they’re horrible as type classes. Try implementing them using interface{} in Go. It’s not the same.
But can also define a closed set of types, perfectly satisfying "sum types".
> This enables different syntax, like the match expression to be used, in which you exhaustively list all the variants.
Go does not provide this out of the box, but that is not prerequisite for sum types. The mathematical theory says nothing about "the compiler must produce an error if the user doesn't match call cases". There is sufficient information provided by the sum types if you wish to add this to your build chain yourself, of course.
This argument feels like the “we have sum types at home” meme. Ergonomics matter.
I write a lot of rust. Rust has traits which are similar to Go’s interfaces. But the features aren’t the same, and I use enum all the time. (I also use trait all the time, but I use trait and enum for different things).
AFAIK, tagged union is sum type, based on sum type mathematical definition.
> People need to learn how to use tools properly.
there is a good chance Rust will start dying and will actually die by being replaced by some new hyper-overengineered lang much faster than C++ actually die.
Also CDDA:Bn wouldn't damn need a > 40h long build using 1.5 GB of RAM under an n270 netbook. Ditto with Nchat, FFS, which is worse. A Golang counterpart for nchat as a TG client (and tdlib rewritten in Go) would weight far less while compiling and maybe even the binary itself, and performance wise it would be similar.
I still remember tons of C++ projects from 2005-2009 impossible to compile today but with GCC 4.3 or GCC 4.9, can't remember. Not because of the size, but because C++ incompatible changes over the years. At least tons of C code will compile it today as is modulo some POSIX changes from C code pre 1996. C++ it's something that should died long ago, among stuff like locales under Unix. UTF8 everywhere, use your own currency and the like.
Yeah, I know, game engines, and tons of physics engines and libraries even FLOSS ones such as OGRE, gdal and the like are C++ domain. Still, most of these could be ported to C.
What's different today really is the LLMs and coding agents. The reason to never rewrite in another language is that it requires you to stop everything else for months or even years. Stopping for two weeks is a lot less likely to kill your project.
In Ladybird's case, tests they could rely upon.
Ladybird appears to have the discipline to have recognized this: “[Rust] is not becoming the main focus of the project. We will continue developing the engine in C++, and porting subsystems to Rust will be a sidetrack that runs for a long time.”
Startups are not a good comparison here. They have a different relationship with code than software projects.
Linux has rewriten entire stacks over and over again.
The PHP engine was rewritten completely at least twice.
The musl libc had entire components rewritten basically from scratch and later integrated.
the hard bit (borrow checker) has still to be done...
Testing has become 10x as important as ever.
I am already using low code tooling with agents for some projects, in iPaaS products.
I have the opposite opinion. As LLM become ubiquitous and code generation becomes cheap, the choice of language becomes more important.
The problem with LLM for me is that it is now possible to write anything using only assembly. While technically possible, who can possibly read and understand the mountain of code that it is going to generate?
I use LLM at work in Python. It can, and will, easily use hacks upon hacks to get around things.
Thus I maintain that as code generation is cheap, it is more important to constraint that code generation.
All of this assume that you care even a tiny bit about what is happening in your code. If you don't, I suppose you can keep banging the LLM to fix that binary blob for you.
As a very practical problem the assembly would consume the context window like no other. And another is having some static guardrails; sometimes LLMs make mistakes, and without guard rails it debugging some of them becomes quite a big workload.
So to keep things efficient, an LLM would first need to create its own programming language. I think we'll actually see some proposals for a token-effective language that has good abstraction abilities for this exact use.
I think, changes to languages/tooling to accomodate Agentic loops will become important.
> All of this assume that you care even a tiny bit about what is happening in your code. If you don't...
I mean, as software engineers, we most certainly do. I suspect there'll be a new class of "developers" who will have their own way of making software, dealing with bugs, building debugging tools that suit their SDLC etc. LLMs will be to software development what Relativity was to Astrophysics, imo: A fundamental & permanent shift.
IMO Rust will strike a very strong balance here for LLMs.
Hardly much different than dealing with traditional offshoring projects output.
I don't understand what you mean. Beat any language at what? Correctness? I don't think that's true at all, but I also don't see how that's relevant, it definitely doesn't address the fact that Rust will virtually always produce faster code than the majority of other languages.
> Hardly much different than dealing with traditional offshoring projects output.
I don't know what you mean here either.
Also there is the alternative path to execute code via agents workestration, just like low code tooling work.
I see you never had the fortune to review code provided by cheap offshoring teams.
I guess that's sort of technically true, but not even really? Like, obviously you can compile Python to C and then compile that with clang, but it doesn't make it fast. But even if that were the case, there aren't that many languages that have Rust performance so who cares? "Potentially" is sort of saying we might have a future language that's better, but of course anyone would agree.
> Also there is the alternative path to execute code via agents workestration, just like low code tooling work.
I don't understand how this is relevant.
> I see you never had the fortune to review code provided by cheap offshoring teams.
I just don't understand why you're bringing it up tbh I don't understand the relevance.
Plenty of AI based tooling is already trying out this path.
Agents execute actions that in the past would be manually programmed applications, now tasks can be automated given a few mcp endpoints.
LLMs are already at the same output quality of lousy offshoring companies, thus having to fix a bit of it is something that unfortunately many of us are already used with fellow humans.
> Well, I am on the provocative side that as AI tooling matures current programming languages will slowly become irrelevant.
And I said I disagree because language directly impacts things like performance. And it does, massively. Like, order of magnitude differences are not hard to achieve simply by changing language.
You are now saying that things just need to be "fast enough", but I don't get how that's relevant. The point is that a different language will have different tradeoffs, and AI changes some of the calculus there, but language is still a major component of the produced artifact. If you agree that language has major implications on the produced artifact, then we agree. If you don't, then I'll just once again appeal to the massive performance gaps between different languages.
I still am not understanding the offshoaring conversation.
But testing in Python is so easy to abuse as LLM. It will create mocks upon mocks of classes and dynamically patch functions to get things going. Its hell to review.
I see the opposite. New languages have more difficulty breaking into popularity due to lack of enough existing codename and ecosystems.
I don't like this bit. Wouldn't it be better to decide on a memory-safe language, and then commit to it by writing all new code in Rust, or whatever. This looks like doing double the work.
I suspect that'll also be what happens here. And if the use of Rust is successful, then over time more components may switch over to Rust. But each component will only ever be in one language at a time.
The Ladybird devs painted themselves in a corner when choosing C++ for a new web browser, with many anti-Rust folks claiming that "modern C++ was safe". Well...
That choice was never made. C++ was selrcted as the language of choice for SerenityOS. Since the goal of the OS was to make its founder happy, and C++ was his faviourite language at the time, that seems like an obvious choice. Later, as part of SerenityOS, there was a need for an HTML parser. It was written in C++ as was the rest of the operating system. Then that HTML parser evolved into a full web browser. As part of the SerenityOS project, that browser was written completely in C++. Then that web browser forked off into an independent project...
Ladybird was already a fully functioning browser (not finished of course but complete enough to surf many web pages) when it was forked from SerenityOS to create a stand-alone web browser. The choice at that point was "keep evolving the current C++ code base" or start-over. I doubt the second option was even considered.
They have been evaluating other languages since before the fork. Rust was evaluated and rejectd early-on. They even created their own language at one point. https://github.com/SerenityOS/jakt
Perhaps, but in fairness the project was started in 2018 when Rust was still new and unproven.
> You can't compare the choices made to evolve a >20 years old codebase with a brand new one.
I guess not, but I'm pretty optimistic about Ladybird's ability to adopt Rust if they want to. It's a much smaller codebase than Firefox (~650K LoC).
This initial PR is already ~25k LoC, so approximately 4% of the codebase. It took 1 person 2 weeks to complete. If you extrapolate from that, it would take 1 person-year to port the whole thing, which is not so bad considering that you could spread that work out over multiple years and multiple people.
And Firefox has shown that the intermediate state where you have a mix of languages is viable over the long term, even in a much larger and more complex codebase.
Thankfully Servo has picked up speed again and if one wants a Rust based browser engine what better choice than the one the language was built to enable?
But I'm also cheering along Ladybird's progress. There's definitely room for more than one project in the space. And IMO the more browsers being built in Rust in the better.
it is totally possible to use some strict subset of C++, which will be memory safe.
I feel like you just know it’s doomed. What this is saying is “I didn’t want to and cannot review the code it generated” asking models to find mistakes never works for me. It’ll find obvious patterns, a tendency towards security mistakes, but not deep logical errors.
The part that concerns me is whether this part will actually come in time or not:
> The Rust code intentionally mimics things like the C++ register allocation patterns so that the two compilers produce identical bytecode. Correctness is a close second. We know the result isn’t idiomatic Rust, and there’s a lot that can be simplified once we’re comfortable retiring the C++ pipeline. That cleanup will come in time.
Of course, it wouldn't be the first time Andreas delivered more than I expected :).
The tests many of us use for how capable a model or harness is is usually based around whether they can spot logical errors readily visible to humans.
No one wants to work with this generated, ugly, unidiomatic ball of Rust. Other than other people using AI. So you dependency AI grows and grows. It is a vicious trap.
My general thoughts on Rust:
- Excellent for short-lived programs that transform input A to output B
- Clunky for long-lived programs that maintain large complex object graphs
- Really impressive ecosystem
- Toxic community