Ladybird adopts Rust, with help from AI • Hacker News Board

Re: Ladybird adopts Rust, with help from AI

#181

Post by codegladiator » Mon, Feb 23, 2026, 2:04 PM UTC

skerit wrote: post #15

> I used Claude Code and Codex for the translation. This was human-directed, not autonomous code generation. I decided what to port, in what order, and what the Rust code should look like. It was hundreds of small prompts, steering the agents where things needed to go. After the initial translation, I ran multiple passes of adversarial review, asking different models to analyze the code for mistakes and bad patterns.…

> This was human-directed, not autonomous code generation.

All my vibe coded projects are human directed, unless explicitly stated otherwise

Re: Ladybird adopts Rust, with help from AI

#182

Post by Imustaskforhelp » Mon, Feb 23, 2026, 2:04 PM UTC

account42 wrote: post #93

potato-peeler wrote: post #83

Is there any discussion on why D or even Ada was not considered? These languages have been around for long time. If they were willing to use llm to break the initial barrier to entry for a new language, then a case can be made for these languages as well.

They already made the mistake picking a niche language twice (first their own language, then Swift as a cross-platform language), why would you want them to make it a third time?

Swift had/has some problems in the language itself. It's not because of the niche nature of Swift that was the problem iirc.

I don't think this is the right response because certainly a meaningful discussion could've definitely taken place and given how they were already open to other languages which was the reason why they picked Swift in the first place.

I remember Andreas video where he talked about how people used rust in his codebase and they were so happy but later it became very difficult whereas they found with swift that it became easier to manage. That was the reason why they picked swift that time.

Certainly their goal wasn't to pick a popular language (because if that's what you want use python or JS) but rather a language that was relevant to what they were building.

So if D and Ada were relevant or not, that's the main point of discussion imo.

Re: Ladybird adopts Rust, with help from AI

#183

Post by dizhn » Mon, Feb 23, 2026, 2:05 PM UTC

djoldman wrote: post #66

A lot of the previous calculus around refactoring and "rewrite the whole thing in a new language" is out the window now that AI is ubiquitous. Especially in situations where there is an extensive test suite. Testing has become 10x as important as ever.

For a personal thing I had AI write some python libraries to power a cli. It has to do with simple excel file filtering, grouping and aggregating. Nothing too fancy. However since it's backed by a library, I am playing with different UIs for the same thing and it's fun to say.. Do it with streamlit. Oh it can't do this particular thing. Fine do it with shiny. No? OK Dash. It takes only like an hour to prototype with a whole new UI library then I get to say "nah" like a spoiled child. :)

Re: Ladybird adopts Rust, with help from AI

#184

Post by mghackerlady » Mon, Feb 23, 2026, 2:05 PM UTC

giancarlostoro wrote: post #158

philipallstar wrote: post #105

Earlier quoted context omitted.

> despite what the haters say 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.

Look at any HN thread that has a project that uses AI in any way, shape or form. People quickly remark that it is slop, without even reviewing the code. If that's not blind hatred of AI, I don't know what is. 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…

Vibe Coding is like porn for programmers. It probably isn't good for you, and you'd probably be better off actually doing the thing yourself, but it feels good and satisfies our desires for instant gratification

Re: Ladybird adopts Rust, with help from AI

#185

Post by the_mitsuhiko » Mon, Feb 23, 2026, 2:06 PM UTC

viktorcode wrote: post #2

> We previously explored Swift, but the C++ interop never quite got there But Rust doesn't have C++ interop at all?

Rust has cxx which I would argue is "good enough" for most use cases. At least all C++ use cases I have. Not perfect, but pretty damn reasonable.

Re: Ladybird adopts Rust, with help from AI

#186

Post by cbondurant » Mon, Feb 23, 2026, 2:06 PM UTC

Based on the origins of Rust as a tool for writing the really thorny, defensive parsers of potentially actively hostile code for firefox, I have to imagine that another web browser is the most at-home place the language could ever be.

Re: Ladybird adopts Rust, with help from AI

#187

Post by thiht » Mon, Feb 23, 2026, 2:06 PM UTC

usrbinenv wrote: post #120

thiht wrote: post #113

Earlier quoted context omitted.

Nobody uses D

And? Does it work? Because it does. It's a lot closer to C++ and you literally need like a week to start being productive and it's insanely flexible as a language. Nobody uses Swift also, but the additional problem with Swift was that it's entirely Apple-centric.

> Nobody uses Swift also

Yep, it was also a weird, not entirely pragmatic choice, even if it was well justified technically and all-in-all rational. D would be the same.

Re: Ladybird adopts Rust, with help from AI

#188

Post by Cyphase » Mon, Feb 23, 2026, 2:07 PM UTC

ursuscamp wrote: post #63

ramon156 wrote: post #38

I'm a long-time Rust fan and have no idea how to respond. I think I need a lot more info about this migration, especially since Ladybird devs have been very vocal about being "anti-rust" (I guess more anti-hype, where Rust was the hype). 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…

They abandoned Swift recently.

The public announcement was less then a week ago. Meanwhile in TFA:

> ... the entire port took about two weeks.

So he was ~halfway in when he made the Swift announcement.

Re: Ladybird adopts Rust, with help from AI

#189

Post by jurschreuder » Mon, Feb 23, 2026, 2:08 PM UTC

Oooh noooo I will have to fork it before it is too late!

Re: Ladybird adopts Rust, with help from AI

#190

Post by surajrmal » Mon, Feb 23, 2026, 2:09 PM UTC

snowhale wrote: post #138

Fervicus wrote: post #123

> 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. I wonder what kind of tech debt this brings and if the trade off will be worth whatever problems they were having with C++.

[dead]

It depends. I migrated a 20k loc c++ project to rust via AI recently and I would say it did so pretty well. There is no unsafe or raw pointer usage. It did add Rc> wasn't very difficult, but keeping the code structure identical at first allowed us to continue to work on the c++ code while the rust port was ongoing and keep the rust port aligned without needing to implement the features twice.

I would say modern c++ written by someone already familiar with rust will probably be structured in a way that's extremely easy to port because you end up modeling the borrow checker in your brain.