Armin Ronacher

With my kids I’m currently building a little dungeron crawler and we’re trying to learn a bit about game development along the way. However given that we live in the modern times of increasing capabilities we wanted to get a narrator and voice over. But we also wanted it to not sound like everyone’s standard AI voices so I looked into what options there are on the table. After some investigation I narrowed down to using Qwen3-TTS which uses voice embeddings for custom voices. With a bit of creativity you can also do more with those custom voices than appears initially. In case this is of inte...

More than a year ago I wrote a few posts here that recommended people not to load custom tools into their context (or MCP servers) but to just use more scripts. Most importantly I wrote that Code Is All You Need and I wrote about that MCP needs code. With Pi 1.0 we now added MCP support via Codemode which in some ways is a long time coming, but then also maybe somewhat surprising to some. So I want to share some updated thoughts on this blog on what this all means. What Are Tools When a harness like Pi provides tools for an LLM to call, it does so by supplying some tool definitions which then...

Serde is an amazing serialization library for Rust and it has been a huge reason why I felt productive with it for years. However already while at Sentry I got quite frustrated with some of the limitations with it but actually replacing Serde is tricky because of the might that it has in the ecosystem. Also because it’s quite hard to actually do better without also making some potentially painful compromises. Here are three examples of Serde corner cases that show poor interactions of Serde features or unexpected limitations: A number that is a map An internally tagged enum, with serde_json‘s...

Yesterday David Sacks wrote a tweet and within a few minutes people did, what they usually do, and they asked Pangram if it was AI. And Pangram said it’s entirely AI generated. To which David replied that these AI detectors are bogus. Now Pangram has a pretty low false positive rate, but if you have ever used an LLM as a writing assitant, you will have probably noticed that it claims your posts 100% AI, even though you don’t feel like they are. Pangram itself is a trained model, that attempts to detect segments of text as being definitely human, definitely AI and a mixture of the two. If you ...

This week some flavor of “AI is going to kill us all” went viral. In particular one where an employee put his personal probability of that happening above 10%. Which made me go to the Wikipedia page of P(doom) and I realized that Dario Amodei’s apparent probability of something bad happening seems to be between 10-25%. And well, Dario then wrote about pacing the frontier . And Sam read it and wants to pace too. And well, so does Musk. I encourage you strongly to read the post, because I think it’s a good one. And yet, when I read the post I could not help but feel in strong opposition to it, ...

I’m more and more convinced that all of AI engineering is Neijuan (内卷, meaning curl inwards). In China it describes a system that demands ever more effort and competition without improving output. The way in which it sometimes shows up in the West is the 996 nonsense. The English term for Neijuan is “Involution” from the book Agricultural Involution. Agricultural involution describes the intensification of farming that raises productivity per square meter while leaving productivity per head unchanged. That’s how I feel about AI right now. Which brings me to GPT 6 Astra. Astra is by all accoun...

A few weeks ago I felt like it would be fun to see if I can make one of those cheap Chinese CarPlay dongles run something other than the stock firmware. The idea was that rather than just forwarding CarPlay, why not do something more interesting with them? They all work quite similarly: they act as bridges between your car and the phone. From there they deal with video and audio streams and pass some other data through. Most of them also bring up a custom UI for pairing and have a web interface that your phone can reach for updates. Long story short: I had a conversation with Fable and Sol vi...

Sean Goedecke wrote a post arguing that you should never be angry at work — a post with which I strongly agree. Anger can be a useful signal, but being angry at work rarely improves the situation. More often, it makes life worse for the people around you, many of whom have no more power over the source of your anger than you do. I did learn that lesson, but it did not come naturally. One thing in particular that I learned is that in a company there is a shared vision, and if you don’t agree with it and are not in a position to change it, you should not start a mutiny, not even a small-scale o...

One of the memes on Twitter is that “programming is solved now.” I’m not sure to what degree it is, but one thing is pretty clear: the act of familiarizing yourself with a language no longer matters and some of the friction that mattered for humans does not matter for agents. As a result, LLMs make language choice much less consequential than it used to be. If you don’t like the choice, you can seemingly rewrite it in another language and you can make it pick a language that you, as a programmer, are entirely unfamiliar with. Which in turn means that people can, and do, choose based on the ma...

A few weeks ago a paper was shared that showed how to extract reasoning traces from closed-weight models. Together with online discussions about tricking models into leaking them, it made me investigate it more out of curiosity. Twitter seems full of half-truths and confusion about how this works, so perhaps this helps some to understand what is happening. Hiding Traces Reasoning traces are usually hidden from us. We have lamented this, but mostly have to accept it. Open-weight models thankfully reveal them, and from their behavior you can see that their traces can be long and confusing. This...