A comment on libxml, not on your work:
Funny how so many companies use this library in production and not one steps in to maintain this project and patch the issues.
What a sad state of affairs we are in.
Yeah I agree, maintaining OS projects has been a weird thing for a long time.
I know a few companies have programs where engineers can designate specific projects as important and give them funds. But it doesn't happen enough to support all the projects that currently need work, maybe AI coding tools will lower the cost of maintenance enough to improve this.
I do think there are two possible approaches that policy makers could consider.
1) There could probably be tax credits or deductions for SWEs who 'volunteer' their time to work on these projects.
2) Many governments have tried to create cyber reserve corps, I bet they could designate people as maintainers of key projects that they rely on to maintain both the projects as well as people skilled with the tools that they deem important.
> I do think there is something interesting to think about here in how coding agents like Claude Code can quickly iterate given a test suite.
This is a point I've tried to advocate for a while. Specially to empower non coders and make them see that we CAN approach automation with control.
Some aspects will be the classic unit or integration tests for validation. Others, will be AI Evals [1] which to me could be the common language for product design for different families/disciplines who don't quite understand how to collaborate with each other.
The amount of progress in a short time is amazing to see.
Please stop spreading this "AI evals" terminology. "evals" is what providers like OpenAI and Anthropic do with their models. If you wrote a test for a feature that uses an LLM, it's just a test, there's no need to say "evals." Having a separate term only further confuses people who already have no idea what that actually means.
Amazing work! I'd love to hear more details about your workflow with Claude Code.
As a side note and this isn't a knock on your project specifically. I think the community needs to normalize disclaimers for "vibe-coded" packages. Consumers really need to understand the potential risks of relying on agent-generated code upfront.
Yeah its a fair point. I wondered if it might be irresponsible to publish the package because it was made this way, but I suspect I'm not the first person to try and develop a package with Claude Code, so I think the best I can do is be honest about it.
As for the workflow, I think the best advice I can give is to setup as many guardrails and tools as possible, so Claude and do as many iterations before needing any intervention. So in this case I setup pre-commit hooks for linting and formatting, gave it access to the full testing suite, and let it rip. The majority of the work was done in a single thinking loop that lasted ~3 hours where Claude was able to run the tests, see what failed, and iterate until they all passed. From there, there was still lots of iterations to add features, clean up, test, and improve performance - but allowing Claude to iterate quickly on it's own without my involvement was crucial.
I agree the wording is a bit strange, but a quick grep of the repo shows that it doesn't imply that.
The only usages of unsafe are in src/ffi, which is only compiled when the ffi feature is enabled. ffi is fundamentally unsafe ("unsafe" meaning "the compiler can't automatically verify this code won't result in undefined behavior") so using it there is reasonable, and the rest of the crate is properly free of unsafe.
Yeah I'm a bit confused because you can have an entirely unsafe code base with just the public interface marked as safe. No unsafe in the interface isn't a measure of safety at all.
It is a measure of the intended level of care that the users of your interface have to take. If there's no unsafe in the interface, then that implies that the library has only provided safe interfaces, even if it uses unsafe internally, and that the interface exposed enforces all necessary invariants.
It is absolutely a useful distinction on whether your users need to deal with unsafe themselves or not.
Sure, it's a useful distinction for whether users need to care about safety but not whether the underlying code is safe itself, which is what I wrote about.
No or very little but verified unsafe internal code is the bar for many Rust reimplementations. It would also be what keeps the code memory safe.
Because it was written in C, libxml2's CVE history has been dominated by use-after-free, buffer overflows, double frees, and type confusion. xmloxide is written in pure Rust, so these entire vulnerability classes are eliminated at compile time.
If by flaws you mean the security researchers spamming libxml2 with low effort stuff demanding a CVE for each one so they can brag about it – no, I don’t think anybody can fix that.
A comment on libxml, not on your work: Funny how so many companies use this library in production and not one steps in to maintain this project and patch the issues. What a sad state of affairs we are in.
Yeah I agree, maintaining OS projects has been a weird thing for a long time.
I know a few companies have programs where engineers can designate specific projects as important and give them funds. But it doesn't happen enough to support all the projects that currently need work, maybe AI coding tools will lower the cost of maintenance enough to improve this.
I do think there are two possible approaches that policy makers could consider.
1) There could probably be tax credits or deductions for SWEs who 'volunteer' their time to work on these projects.
2) Many governments have tried to create cyber reserve corps, I bet they could designate people as maintainers of key projects that they rely on to maintain both the projects as well as people skilled with the tools that they deem important.
> I do think there is something interesting to think about here in how coding agents like Claude Code can quickly iterate given a test suite.
This is a point I've tried to advocate for a while. Specially to empower non coders and make them see that we CAN approach automation with control.
Some aspects will be the classic unit or integration tests for validation. Others, will be AI Evals [1] which to me could be the common language for product design for different families/disciplines who don't quite understand how to collaborate with each other.
The amount of progress in a short time is amazing to see.
- [1] https://ai-evals.io/
Please stop spreading this "AI evals" terminology. "evals" is what providers like OpenAI and Anthropic do with their models. If you wrote a test for a feature that uses an LLM, it's just a test, there's no need to say "evals." Having a separate term only further confuses people who already have no idea what that actually means.
Amazing work! I'd love to hear more details about your workflow with Claude Code.
As a side note and this isn't a knock on your project specifically. I think the community needs to normalize disclaimers for "vibe-coded" packages. Consumers really need to understand the potential risks of relying on agent-generated code upfront.
Yeah its a fair point. I wondered if it might be irresponsible to publish the package because it was made this way, but I suspect I'm not the first person to try and develop a package with Claude Code, so I think the best I can do is be honest about it.
As for the workflow, I think the best advice I can give is to setup as many guardrails and tools as possible, so Claude and do as many iterations before needing any intervention. So in this case I setup pre-commit hooks for linting and formatting, gave it access to the full testing suite, and let it rip. The majority of the work was done in a single thinking loop that lasted ~3 hours where Claude was able to run the tests, see what failed, and iterate until they all passed. From there, there was still lots of iterations to add features, clean up, test, and improve performance - but allowing Claude to iterate quickly on it's own without my involvement was crucial.
> arena-based tree with zero unsafe in the public API
Why "in the public API"? Does this imply it's using unsafe behind the hood? If so, what for?
I agree the wording is a bit strange, but a quick grep of the repo shows that it doesn't imply that.
The only usages of unsafe are in src/ffi, which is only compiled when the ffi feature is enabled. ffi is fundamentally unsafe ("unsafe" meaning "the compiler can't automatically verify this code won't result in undefined behavior") so using it there is reasonable, and the rest of the crate is properly free of unsafe.
Yeah I'm a bit confused because you can have an entirely unsafe code base with just the public interface marked as safe. No unsafe in the interface isn't a measure of safety at all.
It is a measure of the intended level of care that the users of your interface have to take. If there's no unsafe in the interface, then that implies that the library has only provided safe interfaces, even if it uses unsafe internally, and that the interface exposed enforces all necessary invariants.
It is absolutely a useful distinction on whether your users need to deal with unsafe themselves or not.
Sure, it's a useful distinction for whether users need to care about safety but not whether the underlying code is safe itself, which is what I wrote about.
No or very little but verified unsafe internal code is the bar for many Rust reimplementations. It would also be what keeps the code memory safe.
How does it compare to the original in terms of source code size (number of lines of code?)
It's significantly smaller. Because Rust doesn't require header files or memory management, xmloxide is ~40k lines while libxml2 is ~150k lines.
Does it fix the security flaws that caused the original project to be shut down?
Because it was written in C, libxml2's CVE history has been dominated by use-after-free, buffer overflows, double frees, and type confusion. xmloxide is written in pure Rust, so these entire vulnerability classes are eliminated at compile time.
https://gitlab.gnome.org/GNOME/libxml2/-/commit/0704f52ea4cd...
Doesn't seem to have shut down or even be unmaintained. Perhaps it was briefly, and has now been resurrected?
If by flaws you mean the security researchers spamming libxml2 with low effort stuff demanding a CVE for each one so they can brag about it – no, I don’t think anybody can fix that.
Based on context, i kind of imagine they are more thinking of the issues surounding libxslt.