Jax added support for opaque types with custom tangents. One cool use is proper handling of batched geometric objects. Here's a short demo of a differentiable rasterization, i.e. min L2 w/ 1500 triangles to a photo. Interesting to move beyond tensors. (docs.jax.dev/en/latest/hijax…)

Just some personal thoughts now that the AI co-mathematician tech report is public... First, I'm so excited to see the co-mathematician team's hard work out for the world to preview. 💪+🦾=🔥 The team has built a system for mathematicians, with mathematicians. The fact it's now top of the FrontierMath leaderboard is a cherry on top, not the goal. Vibes and utility >> benchmarks. The system is currently being tested with a small number of professional mathematicians. It is not widely available, but I personally hope that, one day, we can get even more capable systems into the hands of all mathematicians. It's been a privilege working with this team at Google DeepMind since January. Props to @dhhzheng, @ADaviesAI, and @pushmeet for their leadership. Give them all a follow to not miss exciting upcoming work.

Announcing Talkie: a new, open-weight historical LLM! We trained and finetuned a 13B model on a newly-curated dataset of only pre-1930 data. Try it below! with @AlecRad and @status_effects 🧵

New work with @AlecRad and @DavidDuvenaud: Have you ever dreamed of talking to someone from the past? Introducing talkie, a 13B model trained only on pre-1931 text. Vintage models should help us to understand how LMs generalize (e.g., can we teach talkie to code?). Thread:

GPT-5.2 derived a novel result in theoretical physics, showing that a type of particle interaction many physicists expected would not occur can in fact arise under specific conditions. There is great promise in the potential of AI to benefit people by accelerating science.

Very happy to be involved in the core training team. Really amazing to see JAX running on our ultra-large scale GPU clusters.

I have to mention this, this opus is reasonably good at low level jax, sharding and pallas. I would call it shard sherrif.

We frictionlessly trained on AMD GPUs and TPUs with a unified JAX framework. Our goodput for flagship runs went past 90%. @YashVanjani @mjcOhio @alokpathy @pcmonk painstakingly removed obstacles to maximize experimental velocity.

Nano Banana Pro: "Generate a diagram of a two-layer neural network in the style of Stephen Biesty"

Unbelievable: the famed Berkeley Math Circle is being forced to shut down due to a bureaucratic requirement where a guest lecturer giving an hour long lesson needs to be officially fingerprinted. How is fingerprinting even still a thing in the 21st century? Chancellor Lyons @richlyons: can you see the absurdity of the situation and figure out a solution? dailycal.org/news/campus/gen…

SGLang now has a pure Jax backend, and it runs natively on TPU!

⛵Marin 32B Base (mantis) is done training! It is the best open-source base model (beating OLMo 2 32B Base) and it’s even close to the best comparably-sized open-weight base models, Gemma 3 27B PT and Qwen 2.5 32B Base. Ranking across 19 benchmarks:

TPU-style collective matmuls on GPU!

Want to improve GPU compute/comms overlap? We just published a new short tutorial for you! A few small changes to the Pallas:MGPU matmul kernel is all it takes to turn it into an all-gather collective matmul that overlaps NVLINK comms with local compute: docs.jax.dev/en/latest/palla…

Curious how to write SOTA performance Blackwell matmul kernels using MGPU? We just published a short step-by-step tutorial: docs.jax.dev/en/latest/palla… At each step, we show exactly what (small) changes are necessary to refine the kernel and the final kernel is just under 150 lines.

Luckily we have alternatives :) github.com/jax-ml/jax/blob/7… Just 100 lines without leaving Python and SOTA performance

Kudos to Terry Tao for this: newsletter.ofthebrave.org/p/…

Today we're putting out an update to the JAX TPU book, this time on GPUs. How do GPUs work, especially compared to TPUs? How are they networked? And how does this affect LLM training? 1/n

So about a month ago, Percy posted a version of this plot of our Marin 32B pretraining run. We got a lot of feedback, both public and private, that the spikes were bad. (This is a thread about how we fixed the spikes. Bear with me. )

Strong recommend for this book and the JAX/TPU docs, even if you are using Torch / GPUs. Clean notation and mental model for some challenging ideas. github.com/jax-ml/scaling-bo… github.com/jax-ml/scaling-bo… docs.jax.dev/en/latest/noteb…