Senior ML Engineer (AI Research, Physical AI)

About Nebius: Nebius is leading a new era in cloud infrastructure for the global AI economy. We are building a full-stack AI cloud platform that supports developers and enterprises from data and model training through to production deployment, without the cost and complexity of building large in-house AI/ML infrastructure. Built by engineers, for engineers. From large-scale GPU orchestration to inference optimization, we own the hard problems across compute, storage, networking and applied AI. Listed on Nasdaq (NBIS) and headquartered in Amsterdam, we have a global footprint with R&D hubs across Europe, the UK, North America and Israel. Our team of 1,500+ includes hundreds of engineers with deep expertise across hardware, software and AI R&D. The role This role is for Nebius AI R&D, a team focused on applied research in AI. Our Physical AI research aims to build intelligent agents that can perceive, reason, and act in the physical world. Research areas include: Vision-language-action models for general-purpose robotic control Reinforcement and imitation learning from human demonstrations, simulation, and real-world experience Scalable collection, generation, and curation of multimodal embodied data Simulation, world models, and sim-to-real transfer Multimodal sensing, including vision, touch, force, and proprioception You will modify large foundation models and learning algorithms for robotic agents, prototype new capabilities in simulation, and validate promising approaches on real-world systems. The results will often lead to collaboration with adjacent research, infrastructure, and engineering teams, where findings are scaled and applied in practice. We are currently looking for senior- and staff-level ML engineers to work on research in areas such as: Vision-language-action models and multimodal foundation models for robotics Reinforcement learning, imitation learning, and learning from demonstrations Scalable acquisition and generation of human, robot, and simulated interaction data World models, planning, and model-based control Sim-to-real transfer, domain adaptation, and robust policy evaluation Dexterous manipulation, whole-body control, and general-purpose robotic agents Some examples of what your responsibilities might include are: Designing, implementing, training, and evaluating large models and learning algorithms for robotic agents Developing vision-language-action architectures that connect multimodal perception and language understanding with physical control Investigating reinforcement learning and imitation learning methods for sparse, delayed, or difficult-to-verify objectives Building scalable methods for incorporating demonstrations, teleoperation data, video, simulation trajectories, and autonomous robot experience into foundation models Designing capture methodologies, datasets, evaluation protocols, and data-quality pipelines for embodied learning Developing simulation environments and conducting sim-to-real experiments on physical robotic platforms Exploring planning, guided generation, and search over action trajectories Prototyping new capabilities in areas such as dexterous manipulation, mobile manipulation, and whole-body control Writing robust research software and distributed training infrastructure that enable rapid experimentation Collaborating with research and engineering teams to translate promising ideas into reliable real-world systems Communicating results through technical reports, open-source releases, demonstrations, and research publications We expect you to have: A profound understanding of the theoretical foundations of machine learning, reinforcement learning, or robot learning Deep expertise in at least one relevant area, such as reinforcement learning, imitation learning, multimodal generative modeling, computer vision, robotics, planning, or control Experience training and evaluating modern deep learning models, including transformer-based or multimodal foundation models Substantial experience training large models across multiple computational nodes Strong software engineering and algorithm-design skills; we primarily use Python Deep experience with a modern deep learning framework; we primarily use JAX Experience designing, executing, and analyzing machine learning experiments with appropriate statistical rigor Ability to formulate meaningful research questions, design experiments that test clear hypotheses, and draw defensible conclusions Experience implementing research ideas and iterating quickly across modeling, data, infrastructure, and evaluation Strong communication and leadership abilities, including the ability to collaborate across research and engineering disciplines Ability to document research findings clearly and contribute to technical reports or research publications Nice to have: Experience working with real-world robots and robotic simulation environments Experience with dexterous manipulation, whole-arm manipulation, mobile manipulation, or humanoid robotics Experience with multimodal sensing, including tactile, force-torque, depth, and proprioceptive signals Experience collecting human demonstrations through teleoperation, motion capture, wearable devices, or observation Experience developing or post-training vision-language models, vision-language-action models, or video and world models Experience with deep reinforcement learning techniques such as offline RL, actor-critic methods, PPO, reward modeling, preference learning, or model-based RL Familiarity with robotics tools and simulators such as MuJoCo, Isaac Sim, Isaac Lab, PyBullet, ROS, or equivalent systems Knowledge of scalable training techniques such as FSDP or ZeRO, FlashAttention, mixed-precision training, quantization, and distributed checkpointing A PhD in Computer Science, Robotics, Machine Learning, Artificial Intelligence, or a related technical field, or equivalent practical experience A track record of impactful publications, open-source contributions, or deployed robotic systems Experience engineering large distributed data-processing, simulation, or model-training systems A record of building and delivering products or research prototypes in a dynamic, startup-like environment Passion for moving research from controlled experiments to capable, reliable real-world robotic systems Excellent command of English, with strong technical writing, presentation, and communication skills Proficiency in contemporary software engineering practices, including version control, testing, code review, and CI/CD Benefits & Perks: Competitive compensation Career growth and learning opportunities Flexibility and ownership Collaborative and innovative culture Opportunity to work on impactful AI projects International environment and talented teams What's it like to work at Nebius: Fast moving - Bold thinking - Constant growth - Meaningful impact - Trust and real ownership - Opportunity to shape the future of AI Equal Opportunity Statement: Nebius is an equal opportunity employer. We are committed to fostering an inclusive and diverse workplace and to providing equal employment opportunities in all aspects of employment. We do not discriminate on the basis of race, color, religion, sex (including pregnancy), national origin, ancestry, age, disability, genetic information, marital status, veteran status, sexual orientation, gender identity or expression, or any other characteristic protected by applicable law. Applicants must be authorized to work in the country in which they apply and will be required to provide proof of employment eligibility as a condition of hire. If you need accommodations during the application process, please let us know.