Junior Member of Entish Staff @apex_ultra_ai Formerly: RS @AIatMeta, DPhil w/ @j_foerst @UniofOxford, Research Intern @GoogleDeepMind, MSc w/ @SchmidhuberAI

London, United Kingdom
Joined May 2022
So happy we're finally out of stealth. It's been enormous fun so far, and the research is still very early. Engineering Superintelligence is close to a blank canvas: there's no playbook yet, the foundational questions are wide open, and the people who work on them now will help define the field. At the centre of those questions is one of the oldest arguments in Western thought. Parmenides held that reality is unchanging and can be reached by pure logic. Heraclitus held that everything is flux: you can't step into the same river twice. Nietzsche called one ice and the other fire [1]. Jeanne Hersch argued that the whole history of philosophy sorts into their two camps [2], and physics does too [3]. The modern round is Wheeler's "it from bit," the idea that reality is built from information, against Landauer's "information is physical": every bit lives in some substrate, and the substrate gets a vote [3]. @SchmidhuberAI sits on both sides. He has argued for decades that the universe could be the output of a program [4], which is about as it-from-bit as (b)it gets, yet he says there's no AGI without mastery of the real world [5]. These aren't contradictory. One is a claim about what the world is, the other about how you come to know it. That second question is the one Engineering Superintelligence has to answer. How much of a real machine can you learn from simulation, and where does physics overrule you? F1 even rations both sides, capping every team's CFD and wind-tunnel time. Maybe we'll settle the debate one day. For now we're deliberately choosing neither ice nor fire, because the opposition is the point. The second law itself came out of engineering: Sadi Carnot, studying steam engines in his Reflections on the Motive Power of Fire [6], showed that an engine needs two reservoirs, one hot and one cold, and that its work comes from the heat flowing between them. Research works the same way. A lab of only bit people, or only it people, sits at equilibrium. Put both in one lab and you have a gradient. Point them at a hard enough problem and it starts doing work. Bit person or it person, come build ESI with us. apexultra.com/join REFERENCES [1] F. Nietzsche, Die Philosophie im tragischen Zeitalter der Griechen (1873) [2] J. Hersch, as recounted in [3], p. 103; see her L'étonnement philosophique (1981) [3] S. Wolf, Epilogue: Information & Physics, in U. Aeschbacher, A. Hansen, S. Wolf, Invitation to Quantum Informatics, vdf ETH (2020), pp. 97-115. doi:10.3218/3989-4 [4] J. Schmidhuber, Algorithmic Theories of Everything (2000). arXiv:quant-ph/0011122 [5] J. Schmidhuber, xitter.cf/SchmidhuberAI/status/2…, itself citing Sec. 20 of arXiv:2212.11279 [6] S. Carnot, Réflexions sur la puissance motrice du feu et sur les machines propres à développer cette puissance, Bachelier, Paris (1824)
Today we come out of stealth. We are Apex Ultra, a frontier AI lab building Engineering Superintelligence (ESI): AI that can design, simulate, test, and build the world's most complex machines. ESI cannot be trained on the open internet. It has to learn where engineering actually happens — against real problems, real physics, and real consequences. Today we can say where one of those places is. @AlpineF1Team has named Apex Ultra its official AI for Engineering Partner. We will train and evaluate ESI against some of the hardest engineering problems in the world, at the pace of Formula One — where every race weekend is a definitive result. The race for ESI is on. 🏁 apexultra.com/alpinef1
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In principle, a hierarchical policy should facilitate both credit assignment and transferability. In practice, HRL algorithms either discard information necessary for control, or retain unnecessary information, limiting experience aggregation for learning. Introducing QSO...
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Very happy to share our recent work on The Agentic Scientist 🧑‍🔬, our next-generation system for orchestrating coding agents for automated scientific (co-)discovery. GitHub: github.com/SakanaAI/AI-Scien… Blog: pub.sakana.ai/agentic-scient… arXiv: arxiv.org/abs/2610.18933 Coding agents are powerful hill-climbers. But to illuminate the space of unknown unknowns, we need systems that can build on previously discovered knowledge, scale open-endedly with resources, and support human co-discovery and evidence-grounded communication. We hope that our system provides a step in this direction.
The Agentic Scientist: Orchestrating Coding Agents for Automated Scientific (Co-)Discovery Blog: pub.sakana.ai/agentic-scient… GitHub: github.com/SakanaAI/AI-Scien… arXiv: arxiv.org/abs/2610.18933 Since 2024, we’ve used The AI Scientist as a way to test how far AI alone can take scientific research, from v1 to v2 to the paper published in Nature earlier this year. The Agentic Scientist is the next step in that line of work, built for the era of coding agents. Coding agents such as Codex and Claude Code now carry out long software tasks on their own. Handing them a research problem, however, tends to produce a strong hyperparameter optimizer rather than a scientist: scores go up, but ideas stay narrow, and the reasons for the gain are rarely examined. The Agentic Scientist makes the research loop explicit. It wraps off-the-shelf coding agents in a scaffold that controls what they see, what they write, how they are evaluated, and how results are handed to the next stage. Parallel workers test hypotheses against rubrics defined before any experiment runs, share successes and failures through a common memory, and then ablate the winning program to generate evidence. We used an early version of the system to study Error Diffusion, a biologically motivated alternative to backpropagation. Our researchers set the question and the rubric, chose directions at each stage, and verified the results, references, and claims before submission. The resulting paper was accepted as an oral presentation at ALIFE 2026. In autonomous runs, the system also raised Doc-to-LoRA retrieval accuracy from 52% to 98% on multi-needle tasks and designed a learned evolution strategy that improves over its CMA-ES reference on unseen tasks. Alongside it we release AutoIllustrate, a pipeline for scientific figures that keeps an editable draw.io file as the source of truth, so every diagram can be corrected by hand. Humans define the question and the standards of evidence; agents expand the experiments researchers can run. We call this Co-Discovery, and we are releasing both systems as open source for the community to build on.
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Today we come out of stealth. We are Apex Ultra, a frontier AI lab building Engineering Superintelligence (ESI): AI that can design, simulate, test, and build the world's most complex machines. ESI cannot be trained on the open internet. It has to learn where engineering actually happens — against real problems, real physics, and real consequences. Today we can say where one of those places is. @AlpineF1Team has named Apex Ultra its official AI for Engineering Partner. We will train and evaluate ESI against some of the hardest engineering problems in the world, at the pace of Formula One — where every race weekend is a definitive result. The race for ESI is on. 🏁 apexultra.com/alpinef1
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Excellent and informative writeup by Roger - and congratulations to him (and OpenAI) for the first artificial agent to beat Craftax! Ironic that the original selling point of high SPS and JAX integration was not even relevant 😅 Lots more interesting work to be done!
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In our Nature paper, we introduce the first superhuman Stratego AI, which we built using general techniques that we developed for RL & test-time compute under imperfect information. 1/N
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Our paper on computer use agents evaluation has been selected for an oral presentation (112 papers among 30709 submissions) at NeurIPS! We took a holistic approach to AI agents evaluation, and worked across the scientific stack (irreverent experiments, theory, statistical framework, conceptual design principles, complex engineering artifacts) to challenge common assumptions while simultaneously advancing fundamental understanding and providing new tools to rigorously benchmark agents. In summary: - Irreverent experiment: we show that in common CUA benchmarks a "replay agent" that just memorizes a frontier model's successful trial can reach state of the art performance when evaluated under common protocols. - Theory: we mathematically prove that the unsettling replay agent is formally the agentification of the pass@k metric that has been often used by the community, exposing the flaws of this metric. - General principles for environment design: we propose a set of general principles (the PRISM principles) to design benchmarks for AI agents, that allow to avoid easy replay and other common problems often found in existing environments. - Digiworld as a showcase of the PRISM principles: we instantiate these principles into a large benchmark for mobile computer use. Digiworld avoids replay agent attacks by automatically generating and checking millions of variations for each one of its apps and tasks. - Statistical framework: to handle this variability, we draw from work on rigorous evaluation for reinforcement learning agents (by Rishabh Agarwal Marc G. Bellemare and others) and build a framework able to accurately estimate an agent's performance by leveraging the structure of a benchmark. - Evaluation of existing models: armed with our new environment and framework, we show that existing frontier models used as CUA agents can be quite brittle to variations of apps and tasks that wouldn't make a big difference for humans (e.g., UI colors). This was extremely fun to work on together with Sneha Silwal, Allen Bolourchi, and other collaborators at Meta Superintellligence Labs. See you at NeurIPS! If you are interested in talking about rigorous evaluation of AI agents, reach out!
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I recently had a had an hour long conversation with @SAIRfoundation - if you are curious about AI Beyond Scaling, @bold_lab_ai , the journey here, and were we are headed this is for you! youtube.com/watch?v=6BZs0bVR… PS: If you'd like to join this journey, the applications for the first ever batch of BOLD Fellows will close at noon UK Time today: jobs.ac.uk/job/DSR362/bold-f…
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Model-free agents learn to maximise reward without modelling the environment. Right? In recent work, we challenge this narrative by proving that agents, trained on a sufficiently rich set of goals, encode a unique and accurate world model in their value functions. 1/
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⛳ Introducing purejaxgcrl: goal-conditioned reinforcement learning in end-to-end JAX for discrete action environments! Train generalist, goal-conditioned agents in minutes on a single GPU. 1/
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Mean Field Games provide a framework for modelling large populations. ICML26 Spotlight: Introducing Recurrent Structural Policy Gradient for partially observable MFGs with common noise, benefitting from faster convergence than model-free RL, but remaining tractable, unlike DP.
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Hindsight Experience Replay has become the ubiquitous method for goal-conditioned reinforcement learning, but leaves open the question of which goal to relabel with. In this work, accepted at ICML, we propose instead simply Learning Everything All at Once (LEO). 1/
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CV has CNNs, NLP has transformers - what inductive bias does RL have? How can policies generalise to regions of the dataset suffering from poor transitions? We motivate hierarchy by enabling distinct state-representations at different levels of the hierarchy @FLAIR_Ox @j_foerst
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Seeing a lot recently about whether info theory explains modern AI. This is *exactly* what our epiplexity paper is about. It shows how to resolve paradoxes around DPI, synthetic data, and emergence, by considering computation and structural info: arxiv.org/abs/2601.03220
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Introducing Hyperagents: an AI system that not only improves at solving tasks, but also improves how it improves itself. The Darwin Gödel Machine (DGM) demonstrated that open-ended self-improvement is possible by iteratively generating and evaluating improved agents, yet it relies on a key assumption: that improvements in task performance (e.g., coding ability) translate into improvements in the self-improvement process itself. This alignment holds in coding, where both evaluation and modification are expressed in the same domain, but breaks down more generally. As a result, prior systems remain constrained by fixed, handcrafted meta-level procedures that do not themselves evolve. We introduce Hyperagents – self-referential agents that can modify both their task-solving behavior and the process that generates future improvements. This enables what we call metacognitive self-modification: learning not just to perform better, but to improve at improving. We instantiate this framework as DGM-Hyperagents (DGM-H), an extension of the DGM in which both task-solving behavior and the self-improvement procedure are editable and subject to evolution. Across diverse domains (coding, paper review, robotics reward design, and Olympiad-level math solution grading), hyperagents enable continuous performance improvements over time and outperform baselines without self-improvement or open-ended exploration, as well as prior self-improving systems (including DGM). DGM-H also improves the process by which new agents are generated (e.g. persistent memory, performance tracking), and these meta-level improvements transfer across domains and accumulate across runs. This work was done during my internship at Meta (@AIatMeta), in collaboration with Bingchen Zhao (@BingchenZhao), Wannan Yang (@winnieyangwn), Jakob Foerster (@j_foerst), Jeff Clune (@jeffclune), Minqi Jiang (@MinqiJiang), Sam Devlin (@smdvln), and Tatiana Shavrina (@rybolos).
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📣 Our recent work at Meta: Rethinking Rubric Generation for Improving LLM Judge and Reward Modeling for Open-ended Tasks Rubric-based judging and reward modeling are powerful for open-ended tasks, but scaling requires controlled generation, not just free-form lists from an LLM.
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In case you missed it over the holidays, we @AIatMeta released: Training AI Co-Scientists using Rubric Rewards. - RL training, we open-source the training and eval datasets! - Human study, finding 70% win-rate - GPT-5's lead in science? Our eval quantifies the anecdotes!
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New work from colleagues at Meta & friends. A step in the co-improving AI direction.
🚨New paper: Training AI Co-Scientists using Rubric Rewards In my recent internship at Meta Superintelligence Labs, I pursued an opinionated research bet: a general, scalable training recipe to improve AI at helping scientists achieve their research goals. Motivation Existing work on training AI for Science optimizes pre-defined, narrow scientific objectives with execution feedback in specially constructed environments (e.g. RLVR). However, it's infeasible to learn from trial and error in many sciences. For e.g. medical research is hard to simulate digitally, and it is unethical to run clinical trials with suboptimal approaches proposed in early training.😬 Moreover, when pursuing a novel research goal, the primary intellectual challenge often lies in defining the experiment setup and objective itself. In the past year, I have increasingly used AI assistance for this (especially GPT-5) in my own research. Of course, models often fail to follow some explicitly stated requirements, and sometimes propose bad design choices, but that is fine! The generated plans are still useful for brainstorming, and I can implement them with further refinement. Method This made us wonder🤔: how can we train models to be better at this task of generating research plans, given an open-ended research goal? For training, we need to collect a large number of research goals, and obtain fast verification signals. Human experts are expensive to access, and that wouldn't scale. 💡Equipped with the vast corpus of openly licensed scientific literature, and the recent success of RL, Synthetic Data Curation, and Rubrics, we propose a scalable recipe: Extract research goals and goal-specific grading rubrics from existing papers with an LLM, and use them for RL training. Specifically, a frozen copy of the initial model rewards the plans generated during training using the goal-specific rubrics, checking seven general guidelines for parts of the plan relevant to each rubric item. 🤔Won't this lead to reward hacking? It will. At some point. But until then, improvements on the training reward might generalize to better research plans for humans. We are hoping the goal-specific rubrics, provided as privileged information to the grader, create a generator-verifier gap that improves research plan generation without external supervision. The only way to find out? Perform a human study. We ask Machine Learning experts to compare plans generated by the finetuned vs initial Qwen3-30B model for ML research goals. This is slow and expensive, it required 45 minutes per annotation to carefully analyze plans, so we could only do this once at the end of the project for evaluation. Results Individual annotations are still noisy, as evaluating research plans is inherently subjective. But sure enough, there is non-trivial signal. The experts preferred (p < 0.01) our finetuned models plans for 70% research goals extracted from NeurIPS'24 / ICLR'25 Oral papers (top 1%) ✅ But only ML, and finetuned vs initial, is boring. Remember, the goal is generality. So we also finetuned Qwen3-30B on goals extracted from medical research, and new arXiv prerints spanning 8 domains. We use rubric evaluations with a jury of frontier models, which also allows us to compare many frontier models across domains. Notable findings: 1) In-domain finetuning leads to 12-22% relative improvements in scores across the three domains: arXiv, medical, and ML 📈 2) Significant cross-domain generalization, especially with the medical finetune improving on ML and new arXiv research goals. This might be evidence for our "generality" thesis 📊 3) Our 30B finetune matches much larger models like Grok-4-Thinking, but GPT-5-Thinking is a cut above the rest (consistent with my qualitative experience) 🤖 Limitations Now of course, LLM-based evaluations, even with a jury and rubrics, are imperfect. But while the individual sample scoring is noisy, we hope for directionally correct results in aggregate, as the jury has positive alignment with human majority vote in our human study on ML. We think the grading scheme holds promise, as optimizing against a much weaker grader (30B), led to improvements in human preference. This work has many such limitations, so treat it more like an early proof-of-concept. We candidly acknowledge them in our paper, and encourage you to scrutinize the details: 📜 alphaxiv.org/abs/2512.23707 Released Artefacts The paper has many ablations and analyses: - our appendix also has sample outputs across domains for vibe-checks, making it 119 pages! - criteria-wise breakdown of performance evolution during training, thanks to our structured grading - SFT on long-form plans worsened model performance - training also improves Gemma, Llama models 🤗We release our train and test data on @huggingface. At a sample-level the data is noisy, and generated by Llama-4-Maverick. Still human experts approved 84% of the rubric items in ML so there's promise, and the same methodology will lead to better quality data as language models improve. Overall, we think the potential of our approach is high: the scientific method is quite general, deep learning benefits from generality (transfer learning), and language models are amazing (better every month!). We hope approaches like this make LMs better at assisting researchers across diverse problem settings and scientific disciplines. Some cool figures from the paper, and acknowledgements in thread🧵. I'm all ears to feedback on how we could've done things better! 1/3
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🚨New paper: Training AI Co-Scientists using Rubric Rewards In my recent internship at Meta Superintelligence Labs, I pursued an opinionated research bet: a general, scalable training recipe to improve AI at helping scientists achieve their research goals. Motivation Existing work on training AI for Science optimizes pre-defined, narrow scientific objectives with execution feedback in specially constructed environments (e.g. RLVR). However, it's infeasible to learn from trial and error in many sciences. For e.g. medical research is hard to simulate digitally, and it is unethical to run clinical trials with suboptimal approaches proposed in early training.😬 Moreover, when pursuing a novel research goal, the primary intellectual challenge often lies in defining the experiment setup and objective itself. In the past year, I have increasingly used AI assistance for this (especially GPT-5) in my own research. Of course, models often fail to follow some explicitly stated requirements, and sometimes propose bad design choices, but that is fine! The generated plans are still useful for brainstorming, and I can implement them with further refinement. Method This made us wonder🤔: how can we train models to be better at this task of generating research plans, given an open-ended research goal? For training, we need to collect a large number of research goals, and obtain fast verification signals. Human experts are expensive to access, and that wouldn't scale. 💡Equipped with the vast corpus of openly licensed scientific literature, and the recent success of RL, Synthetic Data Curation, and Rubrics, we propose a scalable recipe: Extract research goals and goal-specific grading rubrics from existing papers with an LLM, and use them for RL training. Specifically, a frozen copy of the initial model rewards the plans generated during training using the goal-specific rubrics, checking seven general guidelines for parts of the plan relevant to each rubric item. 🤔Won't this lead to reward hacking? It will. At some point. But until then, improvements on the training reward might generalize to better research plans for humans. We are hoping the goal-specific rubrics, provided as privileged information to the grader, create a generator-verifier gap that improves research plan generation without external supervision. The only way to find out? Perform a human study. We ask Machine Learning experts to compare plans generated by the finetuned vs initial Qwen3-30B model for ML research goals. This is slow and expensive, it required 45 minutes per annotation to carefully analyze plans, so we could only do this once at the end of the project for evaluation. Results Individual annotations are still noisy, as evaluating research plans is inherently subjective. But sure enough, there is non-trivial signal. The experts preferred (p < 0.01) our finetuned models plans for 70% research goals extracted from NeurIPS'24 / ICLR'25 Oral papers (top 1%) ✅ But only ML, and finetuned vs initial, is boring. Remember, the goal is generality. So we also finetuned Qwen3-30B on goals extracted from medical research, and new arXiv prerints spanning 8 domains. We use rubric evaluations with a jury of frontier models, which also allows us to compare many frontier models across domains. Notable findings: 1) In-domain finetuning leads to 12-22% relative improvements in scores across the three domains: arXiv, medical, and ML 📈 2) Significant cross-domain generalization, especially with the medical finetune improving on ML and new arXiv research goals. This might be evidence for our "generality" thesis 📊 3) Our 30B finetune matches much larger models like Grok-4-Thinking, but GPT-5-Thinking is a cut above the rest (consistent with my qualitative experience) 🤖 Limitations Now of course, LLM-based evaluations, even with a jury and rubrics, are imperfect. But while the individual sample scoring is noisy, we hope for directionally correct results in aggregate, as the jury has positive alignment with human majority vote in our human study on ML. We think the grading scheme holds promise, as optimizing against a much weaker grader (30B), led to improvements in human preference. This work has many such limitations, so treat it more like an early proof-of-concept. We candidly acknowledge them in our paper, and encourage you to scrutinize the details: 📜 alphaxiv.org/abs/2512.23707 Released Artefacts The paper has many ablations and analyses: - our appendix also has sample outputs across domains for vibe-checks, making it 119 pages! - criteria-wise breakdown of performance evolution during training, thanks to our structured grading - SFT on long-form plans worsened model performance - training also improves Gemma, Llama models 🤗We release our train and test data on @huggingface. At a sample-level the data is noisy, and generated by Llama-4-Maverick. Still human experts approved 84% of the rubric items in ML so there's promise, and the same methodology will lead to better quality data as language models improve. Overall, we think the potential of our approach is high: the scientific method is quite general, deep learning benefits from generality (transfer learning), and language models are amazing (better every month!). We hope approaches like this make LMs better at assisting researchers across diverse problem settings and scientific disciplines. Some cool figures from the paper, and acknowledgements in thread🧵. I'm all ears to feedback on how we could've done things better! 1/3
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