Without being glib, I honestly wonder if Fabrice Bellard has started using any LLM coding tools. If he could be even more productive, that would be scary!

I doubt he is ideologically opposed to them, given his work on LLM compression [1]

He codes mostly in C, which I'm sure is mostly "memorized". i.e. if you have been programming in C for a few decades, you almost certainly have a deep bench of your own code that you routinely go back to / copy and modify

In most cases, I don't see an LLM helping there. It could be "out of distribution", similar to what Karpathy said about writing his end-to-end pedagogical LLM chatbot

---

Now that I think of it, Bellard would probably train his own LLM on his own code! The rest of the world's code might not help that much :-)

He has all the knowledge to do that ... I could see that becoming a paid closed-source project, like some of his other ones [2]

[1] e.g. https://bellard.org/ts_zip/

[2] https://bellard.org/lte/

What I wonder is: are current LLMs even good for the type of work he does: novel, low-level, extremely performant

He has in fact written one: https://bellard.org/ts_server/

> Without being glib, I honestly wonder if Fabrice Bellard has started using any LLM coding tools

I doubt it. I follow him and look at the code he writes and it's well thought out and organized. It's the exact opposite of AI slop I see everywhere.

> He codes mostly in C, which I'm sure is mostly "memorized". i.e. if you have been programming in C for a few decades,

C I think he memorized a long time ago. It's more like he keeps the whole structure and setup of the program (the context) in his head and is able to "see it" all and operate on it. He is so good that people are insinuating he is actually "multiple people" or he uses an LLM and so on. I imagine he is quite amused reading those comments.

Some talented people (mitsuhiko, Evan you) seem to leverage LLM their own way. Probably as legwork mostly.

I think it's the opposite: llms ask Fabrice Bellard instead

Keep in mind even if someone writes their own code LLM is great to accelerate: tests, makefiles, docs, etc.

Or it can review for any subtle bugs too. :)

In 2025, there is no shame in using an LLM. For example, he might use it to get help debugging, or ask if a block of code can be written more clearly or efficiently.

Why every single post in HN has to come down to talk about AI sloop...

Is Fabrice like the Chuck Norris of programming?

> I honestly wonder if Fabrice Bellard has started using any LLM coding tools. If he could be even more productive, that would be scary!

That’s kind of a weird speculation to make about creative people and their processes.

If Caravaggio had had a computer with Photoshop, if Eintein had had a computer with Matlab, would they have been more productive? Is it a question that even makes sense?