{"id":2243417,"url":"https://alion.io/job/nebius-senior-ml-engineer-ai-research","title":"Senior ML Engineer (AI Research)","company":{"id":6364,"name":"Nebius","domain":"nebius.com","url":"https://alion.io/company/nebius","size_band":"1001-5000","is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Greenhouse","truth_index":{"grade":"B","score":84,"open_postings":111,"ghost_share":0,"stale_share":0.631,"repost_share":0,"time_to_fill_p50_days":56,"computed_at":"2026-10-21T05:46:15Z"}},"role":"AI/ML","role_family":"AI/ML","seniority":"senior","employment_type":null,"work_mode":"remote","remote_scope":"stated_regions","remote_scope_basis":"board_field","remote_working_hours":null,"hiring_geo_confidence":"inferred","locations":["Amsterdam, Netherlands","Israel","United Kingdom"],"countries":["NL","IL","GB"],"hiring_countries":["DE","FR","GB","AT","BE","BG","HR","CZ","DK","FI","HU","IE","IL","IT","NL","NO","PL","RO","ES","SE","CH","EE","GR","IS","LV","LI","LT","LU","MT","PT","SK","SI"],"hiring_countries_total":32,"salary":null,"salary_estimate":{"min_usd":124000,"max_usd":321000,"period":"year","method":"global_role_cell_scaled_by_country","sample_n":2216},"experience_years_min":null,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"AI Agents","optional":false},{"name":"Machine Learning","optional":false},{"name":"Model Distillation","optional":false},{"name":"Post-training","optional":false},{"name":"Python","optional":false},{"name":"Reinforcement Learning","optional":false},{"name":"CI/CD","optional":true},{"name":"DPO","optional":true},{"name":"Flash Attention","optional":true},{"name":"FSDP","optional":true},{"name":"LLM","optional":true},{"name":"PPO","optional":true},{"name":"Quantization","optional":true},{"name":"Reward Modeling","optional":true}],"status":"live","first_seen_at":"2025-11-05T16:34:22Z","employer_posted_date":"2026-10-13","last_verified_at":"2026-10-22T04:43:44Z","board_verified":true,"closed_at":null,"days_open":350,"trust":{"level":"stale","repost_count":0,"flags":["stale"],"days_open":350},"description":"About Nebius:\nNebius 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.\nBuilt by engineers, for engineers. From large-scale GPU orchestration to inference optimization, we own the hard problems across compute, storage, networking and applied AI.\nListed 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.\nThe role\nThis role is for Nebius AI R&D, a team focused on applied research in AI. Examples of applied research that we have recently published include:\napplying reinforcement learning for agent training in long-context multi-turn scenarios\ndramatically scaling task data collection to power reinforcement learning for SWE agents\nbuilding a decontaminated evaluation for SWE agents that is regularly updated\ninvestigating how test-time guided search can be used to build more powerful agents\nThe results often lead to collaboration with adjacent teams where our research findings are applied in practice.\nWe are currently looking for senior- and staff-level ML engineers to work on research in areas such as:\nGuided search and reinforcement learning for agentic systems\nReinforcement learning for reasoning models\nWeb-scale problem collection for training agents\nEfficient model distillation\nSome examples of what your responsibilities might include are:\nConducting experiments to figure out efficient ways to train a large language model on traces of interactions with various environments\nExploring methods of guided generation and search in the trajectory space\nComing up with ways to mine relevant data at web scale and figuring out efficient ways to use this data in model post-training\nConducting experiments with different reinforcement learning configurations in verifiable domains\nExploring methods to train AI agents on tasks with non-verifiable reward signals\nWe expect you to have:\nA profound understanding of theoretical foundations of machine learning and reinforcement learning\nDeep expertise in modern deep learning for language processing and generation\nSubstantial experience with training large models on multiple computational nodes\nStrong software engineering skills (we mostly use python)\nDeep experience with modern deep learning frameworks (we use jax)\nStrong communication and leadership abilities\nExperience designing, executing, and analyzing machine learning experiments with proper statistical rigor\nAbility to formulate research questions, design experiments to test hypotheses, and draw meaningful conclusions from results\nAbility to document research findings clearly and contribute to technical publications or report\nNice to have:\nExperience with deep reinforcement learning for LLMs, including techniques such as reward modeling, DPO, PPO etc\nFamiliarity with important ideas in LLM space, such as RoPE, ZeRO/FSDP, Flash Attention, quantization\nBachelor’s degree in Computer Science, Artificial Intelligence, Data Science, or a related field Master’s or PhD preferred\nTrack record of building and delivering products (not necessarily ML-related) in a dynamic startup-like environment\nExperience in engineering complex systems, such as large distributed data processing systems or high-load web services\nOpen-source projects that showcase your engineering prowess\nExcellent command of the English language, alongside superior writing, articulation, and communication skills\nProficiency in contemporary software engineering approaches, including CI/CD, version control and unit testing\nBenefits & Perks:\nCompetitive compensation\nCareer growth and learning opportunities\nFlexibility and ownership\nCollaborative and innovative culture\nOpportunity to work on impactful AI projects\nInternational environment and talented teams\nWhat's it like to work at Nebius:\nFast moving - Bold thinking - Constant growth - Meaningful impact - Trust and real ownership - Opportunity to shape the future of AI \nEqual Opportunity Statement:\nNebius 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.\nApplicants 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. \nIf you need accommodations during the application process, please let us know.","description_format":"text","description_chars":5024,"description_truncated":false,"requirements":{"experience_years_min":null,"management_years_min":null,"team_size_min":null,"manages_managers":false,"education":{"level":"bachelor","optional":false},"security_clearance":false,"languages":[{"language":"English","level":"All levels","optional":true}]},"benefits":[],"hiring_locations":[{"name":"Germany","iso":"DE","kind":"region"},{"name":"France","iso":"FR","kind":"region"},{"name":"United Kingdom","iso":"GB","kind":"country"},{"name":"Austria","iso":"AT","kind":"region"},{"name":"Belgium","iso":"BE","kind":"region"},{"name":"Bulgaria","iso":"BG","kind":"region"},{"name":"Croatia","iso":"HR","kind":"region"},{"name":"Czech Republic","iso":"CZ","kind":"region"},{"name":"Denmark","iso":"DK","kind":"region"},{"name":"Finland","iso":"FI","kind":"region"},{"name":"Hungary","iso":"HU","kind":"region"},{"name":"Ireland","iso":"IE","kind":"region"},{"name":"Israel","iso":"IL","kind":"country"},{"name":"Italy","iso":"IT","kind":"region"},{"name":"Netherlands","iso":"NL","kind":"country"},{"name":"Norway","iso":"NO","kind":"region"},{"name":"Poland","iso":"PL","kind":"region"},{"name":"Romania","iso":"RO","kind":"region"},{"name":"Spain","iso":"ES","kind":"region"},{"name":"Sweden","iso":"SE","kind":"region"},{"name":"Switzerland","iso":"CH","kind":"region"},{"name":"Estonia","iso":"EE","kind":"region"},{"name":"Greece","iso":"GR","kind":"region"},{"name":"Iceland","iso":"IS","kind":"region"},{"name":"Latvia","iso":"LV","kind":"region"},{"name":"Liechtenstein","iso":"LI","kind":"region"},{"name":"Lithuania","iso":"LT","kind":"region"},{"name":"Luxembourg","iso":"LU","kind":"region"},{"name":"Malta","iso":"MT","kind":"region"},{"name":"Portugal","iso":"PT","kind":"region"},{"name":"Slovakia","iso":"SK","kind":"region"},{"name":"Slovenia","iso":"SI","kind":"region"}],"hiring_excludes":[],"relocation_offered":false,"industries":["Artificial Intelligence","Data Centers & Colocation","Cloud Platforms (IaaS & PaaS)","AI Compute & Inference"],"lifecycle":[{"event":"open","at":"2026-10-11T01:05:42Z"}],"visa":[],"liveness":{"score":6,"band":"cold","label":"Long shot","p_open":1,"p_active":0.215,"p_room":0.28,"age_days":349,"expected_fill_days":56,"reasons":["conf:2","stale_co","velocity","win:tail","crowd:brand"],"computed_at":"2026-10-21T05:46:15Z"},"pay":null,"html_url":"https://alion.io/job/nebius-senior-ml-engineer-ai-research","json_url":"https://alion.io/job/nebius-senior-ml-engineer-ai-research.json","meta":{"generated_at":"2026-10-22T05:58:56Z","cache_seconds":300,"methodology":"https://alion.io/methodology","terms":"https://alion.io/terms","contact":"https://alion.io/contact","api":"https://alion.io/developers","about":"Alion is a live layer of people, companies and AI agents: who they are, whether they are real and active right now, what they do and how to work with them, readable by people and by agents and paid per call.","catalog":"https://alion.io/catalog.json","usage":{"tier":"crawler_verified","counted_by":"address","units_charged":1,"used_today":627,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-10-23T00:00:00Z"}},"offers":[{"id":"company.slices","title":"One company in depth, by slice","status":"live","price":{"credits":0.02,"usd":0.002,"plus_per_slice":{"credits":0.05,"usd":0.005}},"unit":"per company, plus each slice with data","note":"the employer in depth","call":{"mcp_tool":"get_company","arguments":{"id":6364},"rest":"https://alion.io/mcp/rest/get_company?id=6364"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Fnebius-senior-ml-engineer-ai-research"},{"id":"market.stats","title":"A market slice: pay, demand and time to fill","status":"live","price":{"credits":1,"usd":0.1},"unit":"per slice","note":"pay, demand and time to fill for this role and place","call":{"mcp_tool":"market_stats"},"human":"https://alion.io/catalog?offer=market.stats&for=job%2Fnebius-senior-ml-engineer-ai-research"},{"id":"job.search","title":"Open jobs by role, technology, place, pay and visa","status":"live","price":{"credits":0.02,"usd":0.002},"unit":"per posting in a list","note":"similar open postings","call":{"mcp_tool":"search_jobs"},"human":"https://alion.io/catalog?offer=job.search&for=job%2Fnebius-senior-ml-engineer-ai-research"},{"id":"company.verify","title":"Is this company real and active right now","status":"pilot","price":null,"unit":"per company","request":{"url":"https://alion.io/catalog/request","method":"POST","body":"{\"offer\": \"company.verify\", \"for\": \"job/nebius-senior-ml-engineer-ai-research\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Fnebius-senior-ml-engineer-ai-research"}]}