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Claude Code can debug low-level cryptography

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11–20 of 217 posts

Re: Claude Code can debug low-level cryptography

#11
Using coding agents to track down the root cause of bugs like this works really well:

> Three out of three one-shot debugging hits with no help is extremely impressive. Importantly, there is no need to trust the LLM or review its output when its job is just saving me an hour or two by telling me where the bug is, for me to reason about it and fix it.

The approach described here could also be a good way for LLM-skeptics to start exploring how these tools can help them without feeling like they're cheating, ripping off the work of everyone who's code was used to train the model or taking away the most fun part of their job (writing code).

Have the coding agents do the work of digging around hunting down those frustratingly difficult bugs - don't have it write code on your behalf.

Re: Claude Code can debug low-level cryptography

#12
post #4

CLI terminals are incredibly powerful. They are also free if you use Gemini CLI or Qwen Code. Plus, you can access any OpenAI-compatible API(2k TPS via Cerebras at 2$/M or local models). And you can use them in IDEs like Zed with ACP mode. All the simple stuff (creating a repo, pushing, frontend edits, testing, Docker images, deployment, etc.) is automated. For the difficult parts, you can just use free Grok to one-s…

How good is Gemini CLI compared to Claude code and openAi codex?

Gemini and it's tooling is absolute shit. The LLM itself is barely usable and needs so much supervision you might as well do the work yourself. Then couple that with an awful cli and vscode interface and you'll find that it's just a complete waste of time.

Compared to the anthropic offering is night and day. Claude gets on with the job and makes me way more productive.

Re: Claude Code can debug low-level cryptography

#13
post #6

Earlier quoted context omitted.

How good is Gemini CLI compared to Claude code and openAi codex?

I started with Claude Code, realized it was too much money for every message, then switched to Gemini CLI, then Qwen. Probably Claude Code is better, but I don't need it since I can solve my problems without it.

Yeah I was using openrouter for Claude code and burned through $30 in credits to do things that if I had just used the openrouter chat for it would have been like $1.50, I decided it was better for now to do the extra “secretary work” of manual entry and context management of the chat and pain of attaching files. It was pretty disappointing because at first I had assumed it would not be much different in price at all.

Re: Claude Code can debug low-level cryptography

#14
I'm not surprised it worked.

Before I used Claude, I would be surprised.

I think it works because Claude takes some standard coding issues and systematizes them. The list is long, but Claude doesn't run out of patience like a human being does. Or at least it has some credulity left after trying a few initial failed hypotheses. This being a cryptography problem helps a little bit, in that there are very specific keywords that might hint at a solution, but from my skim of the article, it seems like it was mostly a good old coding error, taking the high bits twice.

The standard issues are just a vague laundry list:

- Are you using the data you think you're using? (Bingo for this one)

- Could it be an overflow?

- Are the types right?

- Are you calling the function you think you're calling? Check internal, then external dependencies

- Is there some parameter you didn't consider?

And a bunch of others. When I ask Claude for a debug, it's always something that makes sense as a checklist item, but I'm often impressed by how it diligently followed the path set by the results of the investigation. It's a great donkey, really takes the drudgery out of my work, even if it sometimes takes just as long.

Re: Claude Code can debug low-level cryptography

#15
post #12

Earlier quoted context omitted.

How good is Gemini CLI compared to Claude code and openAi codex?

Gemini and it's tooling is absolute shit. The LLM itself is barely usable and needs so much supervision you might as well do the work yourself. Then couple that with an awful cli and vscode interface and you'll find that it's just a complete waste of time. Compared to the anthropic offering is night and day. Claude gets on with the job and makes me way more productive.

> Gemini and it's tooling is absolute shit.

Which model were you using? In my experience Gemini 2.5 Pro is just as good as Claude Sonnet 4 and 4.5. It's literally what I use as a fallback to wrap something up if I hit the 5 hour limit on Claude and want to just push past some incomplete work.

I'm just going to throw this out there. I get good results from a truly trash model like gpt-oss-20b (quantized at 4bits). The reason I can literally use this model is because I know my shit and have spent time learning how much instruction each model I use needs.

Would be curious what you're actually having issues with if you're willing to share.

Re: Claude Code can debug low-level cryptography

#16
post #2

This resonates with me a lot: > As ever, I wish we had better tooling for using LLMs which didn’t look like chat or autocomplete I think part of the reason why I was initially more skeptical than I ought to have been is because chat is such a garbage modality. LLMs started to "click" for me with Claude Code/Codex. A "continuously running" mode that would ping me would be interesting to try.

I absolutely agree with this sentiment as well and keep coming back to it. What I want is more of an actual copilot which works in a more paired way and forces me to interact with each of its changes and also involves me more directly in them, and teaches me about what it's doing along the way, and asks for more input. A more socratic method, and more augmentic than "agentic". Hell, if anybody has investment money an…

I'm working on such a thing, but I'm not interested in money, nor do I have money to offer - I'm interested in a system which I'm proud of.

What are your motivations?

Interested in your work: from your public GitHub repos, I'm perhaps most interested in `moor` -- as it shares many design inclinations that I've leaned towards in thinking about this problem.

Re: Claude Code can debug low-level cryptography

#17
post #6

Earlier quoted context omitted.

How good is Gemini CLI compared to Claude code and openAi codex?

I started with Claude Code, realized it was too much money for every message, then switched to Gemini CLI, then Qwen. Probably Claude Code is better, but I don't need it since I can solve my problems without it.

I've found the regular Claude Pro subscription quite enough for coding tasks when you anyway have a bunch of other things like code reviews to do in addition to coding, and won't spend the whole day running it.

Re: Claude Code can debug low-level cryptography

#19
Personally my biggest piece of advice is: AI First.

If you really want to understand what the limitations are of the current frontier models (and also really learn how to use them), ask the AI first.

By throwing things over the wall to the AI first, you learn what it can do at the same time as you learn how to structure your requests. The newer models are quite capable and in my experience can largely be treated like a co-worker for "most" problems. That being said.. you also need to understand how they fail and build an intuition for why they fail.

Every time a new model generation comes up, I also recommend throwing away your process (outside of things like lint, etc.) and see how the model does without it. I work with people that have elaborate context setups they crafted for less capable models, they largely are un-neccessary with GPT-5-Codex and Sonnet 4.5.

Re: Claude Code can debug low-level cryptography

#20
post #18

As declared by an expert in cryptography who knows how to guide the LLM into debugging low-level cryptography, which that's good. Quite different if you are not a cryptographer or a domain expert.

Even the title of the post makes this clear: it's about debugging low-level cryptography. He didn't vibe code ML-DSA. You have to be building a low-level implementation in the first place for anything in this post to apply to it.
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