[skerit]

> 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. > The requirement from the start was byte-for-byte identical output from both pipelines. The result was about 25,000 lines of Rust, and the entire port took about two weeks. The same work would have taken me multiple months to do by hand. 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. Zero regressions across the board

This is the way. Coding assistants are also really great at porting from one language to the other, especially if you have existing tests.

[patates]

> Coding assistants are also really great at porting from one language to the other

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.

[josephg]

> 10/10 - would generate tens of thousands of lines of useless code again.

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!

[uyzstvqs]

> It burned through a mountain of tokens, but 10/10 - would generate tens of thousands of lines of useless code again.

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.

[tasuki]

> a relic from the days when everyone thought Drupal was the future (long time ago).

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...

[oblio]

> It burned through a mountain of tokens, but 10/10 - would generate tens of thousands of lines of useless code again.

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 :-)

[pjmlp]

There are plenty of SMEs trapped into that future. :)

[embedding-shape]

Agree, and it's also such a shame that none of the AI companies actually focus on that way of using 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.

[dsr_]

Is it any surprise that the cocaine cartels really want you to buy more cocaine, so they don't focus on its usefulness in pain relief and they refine it and cut it with the cheapest substances that will work rather than medical-grade reagents?

Same thing.

[freeopinion]

Of course there are tools focusing on this. It takes a little getting used to how prevalent it is. My editor now can anticipate the next three lines of code I intend to write complete with what values I want to feed to the function I was about to invoke. It all shows up in an autocomplete annotation for me. I just type the first two or three characters and press tab to get everything exactly how I was about to type it in--including an accurate comment worded exactly in my voice.

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?

[Thanemate]

>Agree, and it's also such a shame that none of the AI companies actually focus on that way of using AI.

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.

[mghackerlady]

I think it was Steve Jobs who said computers should be like a bicycle for the mind, I tend to agree

[JetSetIlly]

"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 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.

[blibble]

> Agree, and it's also such a shame that none of the AI companies actually focus on that way of using AI.

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

[otikik]

I am learning rust myself and one of the things I definetly didn't want to do was let Claude write all the code. But I needed guidance.

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".

[philipportner]

FYI: Claude has output styles, one of them is called `learning`. Instead of writing the code itself, it will add `TODO(human)` and comments to explain how to. Also adds `Insights` explaining concepts to you in its output.

This link also has a comparison to Skills further down.

https://code.claude.com/docs/en/output-styles#built-in-outpu...

[dwood_dev]

I had a bash spaghetti code script that I wrote a few years ago to handle TLS certificates(generate CSRs, bundle up trust chains, match keys to certs, etc). It was fragile, slow, extremely dependent on specific versions of OpenSSL, etc.

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.

[giancarlostoro]

This is also how some of us use Claude despite what the haters say. You dont just go “build thing” you architect, review, refine, test and build.

[gnfargbl]

It's how most of us are actually going to end up using AI agents for the foreseeable future, perhaps with increasing degrees of abstraction as we move to a teams-of-agents model.

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.

[latexr]

> how some of us

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.

[philipallstar]

> 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.

[scuff3d]

We keep seeing this pattern over and over as well. Despite LLM companies' almost tangible desperation to show that they can replace software engineers, the real value comes from domain experts using the tools to enhance what they're already good at.

[wwweston]

I'd guess this is a bet on which market is more lucrative:

* domain experts paying for tooling that will enhance their productivity

* capital/management class hoping to significantly replace domain experts

Software devs have been a famously tough market to sell tools to for a long time, so the better bet is B. Plus, the story on B is fantastic for fundraising; if there's a 10% chance that it checks out, you want some part of that as your capital portfolio.

[staticassertion]

I had a script in another language. It was node, took up >200MB of RAM that I wanted back. "claude, rewrite this in rust". 192MB of memory returned to me.

[zozbot234]

Solving the big RAM shortage one prompt at a time.

[ricardobeat]

This is sad to see. Node was originally one of the memory efficient options – it’s roots are solving the c10k problem. Mind sharing what libraries/frameworks you were using?

[vunderba]

I used to have a bunch of bespoke node express server utilities that I liked to keep running in the background to have access to throughout the day but 40-50mb per process adds up quickly.

I’ve been throwing codex at them and now they’ve all been rewritten in Go - cut down to about 10mb per process.

[bee_rider]

I haven’t done a ton of porting. And when I did, it was more like a reimplementation.

> 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.

[tinco]

My company helps companies do migrations using LLM agents and rigid validations, and it is not a surprising goal. Of course most projects are not as clean as a compiler is in terms of their inputs and outputs, but our pitch to customers is that we aim to do bug-for-bug compatible migrations.

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..

[adw]

It’s a very good way of getting LLMs to work autonomously for a long time; give it a spec and a complete test suite, shut the door; and ask it to call you when all the tests pass.

[einpoklum]

> Coding assistants are also really great at porting from one language to the other

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.

[hsaliak]

This is the way. This exact workflow is my sweet spot.

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.

[crashabr]

This is broadly how I worked when I was still using chat instead of cli agents for LLM support. The downside, I feel, is that unless this is a codebase / language / architecture I do not know, it feels faster to just code by hand with the AI as a reviewer rather than a writer.

[tarasglek]

your patch queue approach is very clever. Solves a huge tech debt poblem with llm code gen. Should work with jujitsu too probably.

Would be curious to see more about how you save tokens with lua too.

Do you blog?

[qwm]

I did this exact same thing for porting a compiler from one language to another with Codex. I run tests at every step, and verified that bytecode output was byte-for-byte identical. I was very impressed at the results, and this is coming from someone who's always pointing out issues with AI programming.

[codegladiator]

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

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

[polyterative]

I am having immense success with the latest models developing a personal project that I open sourced and then got burned off by.I can't write anymore by hands but I do enjoy writing prompts with my voice.I have been shipping the best code the project has ever seen.The revolution is real.

[Aurornis]

Coding assistants are great at pattern matching and pattern following. This is why it’s a good idea to point them at any examples or demos that come with the libraries you want to use, too.

[xhkkffbf]

If every AST is isomorphic, why bother? Don't you miss getting some of the advantages of Rust?

[nu11ptr]

Quite good. I ported my codebase from Go to Rust in a fraction of the time it would have taken me to rewrite it.

[nz]

How does he solve the Fruit of the Poison Tree problem? For all he know, his LLMs included a bunch copyrighted or patented code throughout the codebase. How is he going to convince serious people that this port is not just a transformation of an _asset_ into a _liability_?

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.).

[DANmode]

One or both of you have the story very wrong.

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…