PhD Student in ML @ICepfl MLO. MSc/BSc from @ETH_en. Previously: Fellow @AnthropicAI, Student Researcher @Apple MLR.

Lausanne, Switzerland
Joined January 2020
New research from our MLO Lab @EPFL: Improving Neural Network Training by Decoupling the Magnitude and Direction of Weight Vectors. Magnitude-Direction Decoupling (MD): a simple optimizer tweak, and what we (currently) think is the right way to train efficiently at scale. 🧵
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Alex Hägele retweeted
Can a language model be based purely on self-conditioning? 🤔 Yes! Meet LAW 👋 (a.k.a. Loopholing All the Way!) 🧵1/8
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If you're not surprised, you didn't understand it…🙃 Turns out we can train generative models purely through self-conditioning! Really happy with the outcome of this collaboration! Huge thanks to @nadjushenka_, @DeschenauxAdri, @jdeschena, and the rest of the team! 🙌
Can a language model be based purely on self-conditioning? 🤔 Yes! Meet LAW 👋 (a.k.a. Loopholing All the Way!) 🧵1/8
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Your neo-lab wants to pre-train a frontier model, but no provider will sell you enough co-located chips? We got you. Our new work shows that SOAP & SPlus achieve strong worker scaling to 96+ DiLoCo workers (e.g., 96 providers) by whitening the update’s covariance. 🧵1/9
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new paper (and last one from my postdoc): arxiv.org/abs/2610.16518 we analyze WSD schedules for least-squares problems. this is excellent work from Noé, who lead this paper during his internship at Inria, together with @BachFrancis .
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here we go again
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Apertus 1.5 Technical Report is out! 134 pages of fully open multimodal reasoning model development from Swiss AI Initiative (ETH Zurich/EPFL) with data recipe, training experiments and many interesting insights 🇨🇭 Thread with my personal coverage ⬇️
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Alex Hägele retweeted
The Apertus 1.5 report is finally out! 👇 We learnt a lot building this model: from biases in SFT data to the challenges of scaling RL infrastructure and controlling model outputs during RLVR. Follow @apertusllm for more updates! Paper: arxiv.org/pdf/2610.15542 HF: huggingface.co/collections/s…
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Apertus 1.5 tech report (134 pages!) finally out:
134 pages from ETH and EPFL on training a multimodal reasoning model I’ve had a lot of fun putting off various fires there, given the fully open source and data requirements, you won’t find a better report, especially a multimodal one
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Alex Hägele retweeted
134 pages from ETH and EPFL on training a multimodal reasoning model I’ve had a lot of fun putting off various fires there, given the fully open source and data requirements, you won’t find a better report, especially a multimodal one
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Our tech report just dropped 👇
134 pages from ETH and EPFL on training a multimodal reasoning model I’ve had a lot of fun putting off various fires there, given the fully open source and data requirements, you won’t find a better report, especially a multimodal one
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Alex Hägele retweeted
The Bitter Lesson for harness design and formal math! Instead of hand-designing how an AI should prove (decompose, plan, assign agents), what if we just give a frontier model good Lean feedback and let it keep working? We built h1. TL;DR: → SOTA on formal theorem proving benchmarks → can solve open conjectures → matches/beats hand-designed workflows → one long attempt can beat many retries [1/7]
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Alex Hägele retweeted
Factuality evals need a rethink; here's why: openreview.net/pdf?id=181wn4… (Grateful that this won the Best Paper Award at the Scientific Understanding of Foundation Models workshop @ COLM. Joint work with @im_td and @caglarml)
Replying to @wen_kaiyue
3/ 🏆 Best Paper The Future of Facts: Tracing the Factual Generation-Verification Gap @im_td @AnjaSurina @caglarml openreview.net/forum?id=181w…
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Say hi to PUMBA! 🐗 Masked diffusion language models are trained one way and sampled another. Our new paper studies how to make MDM training more aware of the trajectories followed at inference, and how this can lead to more efficient text generation. Paper link below 🧵
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Alex Hägele retweeted
Transformers use the same hidden state for two competing roles: maintaining state and predicting the next token. 🔀 Splitting these roles into two separate streams outperforms standard Transformers. Introducing the State-Prediction Separation (SPS) Transformer. 🧵
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The Apertus team, a group of researchers at EPFL, ETH Zurich, and the Swiss National Supercomputing Centre (CSCS), partners with Swiss technology company Proton to make Apertus 1.5 available in Lumo, Proton’s AI assistant. actu.epfl.ch/news/apertus-pa…
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Working at a Swiss NGO or non-profit and curious about using AI? Join a hands-on workshop at EPFL to explore Apertus, learn how it can be deployed on your own infrastructure, and share your needs with the team building it. Get a spot: luma.com/k910o3e1 @SDSCdatascience
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🇨🇭 Sovereign Open-Source AI in Action: Switzerland’s Apertus 1.5 is now integrated into Proton’s Lumo. Starting today, Apertus 1.5 (the open language model built by EPFL, ETH Zurich, and CSCS) is available as an optional model inside Proton’s privacy first assistant, Lumo. ◾️Truly Open Science: Trained on the Alps supercomputer under the Swiss AI Initiative, Apertus is released under Apache 2.0 (8B and 70B sizes). Version 1.5 brings vision capabilities, a 262k context window, a thinking mode, and upgraded tool use. ◾️Sovereignty in Practice: By keeping infrastructure, data, and compute within national borders, Switzerland ensures technological independence from global big tech monopolies. ◾️Privacy by Design: Lumo users can opt into Apertus while maintaining Proton’s zero access encryption. Switzerland is quietly building a blueprint for sovereign, open source AI. Apertus isn't trying to replace every closed system overnight, it's establishing a real, privacy respecting pipeline from supercomputer to consumer application. #SovereignAI #OpenSourceAI #Privacy #SwissAI #ArtificialIntelligence #TechInnovation @cervisiarius @EPFL @TrustValleyCH @LuizaJarovsky @ImanolSchlag @xavierstuder @haeggee @cscsch @AbtSwitzerland @EPFL_AI_Center @DominiqueCAPaul @BrianRoemmele @clara__meister @effi288 @JulienFrrr @AnneLaureBEAUD2 @valentina__py @MLoebekken @alan_frei @ProtonPrivacy @SwissDevJobs @emmanuel_belo @USchuepbach @tagesanzeiger @GH_Wiegand @apertusllm @a_yukh @ETH_AI_Center @ETH @EPFL_AI_Center
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Alex Hägele retweeted
Probably the most ambitious project on alignment by an academic lab. And probably one of the most fun places to work with some really amazing colleagues
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Alex Hägele retweeted
Our new paper shows that optimizer memory schedules can *outscale* AdamW across the overtraining axis…in Transformers! Joint work with @ShikaiQiu 🧵
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At Marin we’ve found that scaling laws let us simulate the entire training trajectory. This became clear in our last 67B MoE run. The run hit the loss target within 1%, but perhaps more interestingly, arbitrary points during training could also be predicted to within 1%. This model is finishing up long context and will soon enter RL. Based on this finding, we’ve used a scaling ladder to simulate the training trajectory of the 535B MoE we kicked off yesterday. Will see how it goes. Now if someone can figure out how to fit a scaling law to each parameter we can just predict our final model and skip this training business. Something else I've learned from this process is that getting a training run off the ground is way more than just fiddling with the architecture. Lot of herculean efforts from teammates to get trillions of tokens curated, get hardware running on a new GPU stack, improve MFU, and propose great ideas that were tested and integrated. Given that this is our largest run to date, I anticipate lots of learning and adapting along the way. But thats part of the fun. Details: github.com/marin-community/m…
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