AlphaProof Paper

Thu 13 November 2025

I'm very excited to finally be able to share more details about how AlphaProof works! AlphaProof is the system that we used to discover the Lean proofs for the International Mathematical Olympiad 2024, reaching silver medal performance. Our full paper Olympiad-Level Formal Mathematical Reasoning with Reinforcement Learning has now been published in Nature.

: The work described was done from the beginning of 2022 to July 2024, while I was still at Google DeepMind.

The International Mathematical Olympiad

The International Mathematical Olympiad, or IMO for short, is a yearly contest in mathematics amongst the 6 ...

MAD Podcast

Sat 25 October 2025

This week I had the pleasure of chatting with Matt Turck from the MAD Podcast, and it was a fun one! We talked trends in AI, RL and why it unlocks Agents, scaling and so much more.

You can find the episode on your podcast app of choice, or on YouTube:

For the curious, some links to what we talked about, and further reading:

• my recent blog post, Failing to Understand the Exponential
• Move 37, as ...

Python 3.14 - Threading Unbound

Wed 08 October 2025

Python 3.14 is released and I’m extremely exited that free-threading is now officially supported! Finally no more GIL, finally able to use all the hundreds of cores on modern servers! Or at least in theory, we'll see how it holds up in practice.

I'm also quite excited for template string literals (t-strings). Better HTML templates? Direct SQL interpolation? I'm looking forward to what the community comes up with.

Many packages already provide free-threaded wheels, including core ML libraries such as numpy, jax and torch. This means it's now easy to parallelize your data pipeline, without any multiprocessing!

...

Failing to Understand the Exponential, Again

Sat 27 September 2025

The current discourse around AI progress and a supposed “bubble” reminds me a lot of the early weeks of the Covid-19 pandemic. Long after the timing and scale of the coming global pandemic was obvious from extrapolating the exponential trends, politicians, journalists and most public commentators kept treating it as a remote possibility or a localized phenomenon.

Something similarly bizarre is happening with AI capabilities and further progress. People notice that while AI can now write programs, design websites, etc, it still often makes mistakes or goes in a wrong direction, and then they somehow jump to the conclusion ...

Giving Advice

Sat 27 September 2025

Good advice should rule out large parts of the possibility space - if you don't find yourself disagreeing with the advice or changing what you are doing, then the advice is just generic fluff.

Advice should be based on experience. Not necessarily your own, observing others can also make good advice, and it scales a lot better.

Good advice is contentious or not widely known. If everyone agrees with it already it’s just common sense.

It's often easier to give advice on what not to do, rather than on what you should do. It's less useful, but ...

Disconnect on Holiday

Wed 10 September 2025

A timely topic, as I'm writing this on the plane back from my latest trip: When you go on holiday, don’t check your work email, disable all notifications, just disconnect completely. Not just for your own mental health - many people have covered that extensively - but also to test the resilience of your work projects.

It’s easy to argue about bus factors, but nothing clarifies the situation better than going off grid for two weeks. Can your colleagues add new features, fix bugs with ease? Or do they start wishing for you to come back, try to contact ...

New Domain

Wed 13 August 2025

After almost 18 years with my old domain (furidamu.org, acquired August 2007!), I found a new domain that should be easier to remember and spell: julian.ac

I've migrated my blog to the new domain, but I plan to keep the old domain and URLs active indefinitely, with redirects to the corresponding new address. Please let me know if you run into any issues!

I was also tempted by a second domain, julian.photo, to finally get more serious about editing and sharing my travel and animal photos. This project is still very much work in progress, I'm experimenting ...

Serverless Comments

Sat 09 August 2025

While migrating my blog to my new domain (julian.ac!), I realized that the service I had been using for comments had not been maintained in a while, and did not support easy migration to a new domain.

I've been very impressed with the simplicity and reliability of S3 in the >10 years I've been using it to host this blog, so why not use the same setup for comments? It's not like I need to support massive write throughput or millions of comments, so a very simple system is sufficient:

• All comments for a post are stored ...

Slimming Down

Sun 20 July 2025

This morning I got nerd-sniped by Why your website should be under 14kB in size. I had already optimized my blog several times previously, most recently writing my own static site generator in Rust, but according to the Cloudflare URL Scanner my front page was still a shocking 242 kB!

How could this be? Turns out 124 kB were consumed just by highlight.js, and a further 75 kB by a single screenshot from one of my posts. And this wasn't even counting another 258 kB from KaTeX, which failed to load in the Cloudflare scanner due to the CORS ...

HDR Photography

Mon 26 May 2025

Estimates for the dynamic range (the maximum perceivable contrast between light and dark) of human eyes vary depending on the source, from 1:100 to 1:1000 or more for static contrast. Dynamic contrast, where the eye moves around the scene and the iris adjusts in size is many orders of magnitude larger - with sufficient adaption time we can switch between bright daylight (${10}^{8}cd/m^2$) and faint starlight (${10}^{-6}cd/m^2$), a range of ${10}^{14}$!

In comparison, standard computer screens display images encoded using 8-bit color channels, for a maximum of 256 brightness levels. This is why photos of very vivid ...