Staff Applied AI Researcher (Agentic Search) in London

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. We are seeking a Staff Applied AI Researcher to join a fast growing team building an agent native search platform - the web access layer for AI systems. You can think of this as Google for AI agents: a system designed for machines, not humans. We are building agentic search, where AI systems actively plan, retrieve, evaluate, and refine information rather than simply returning results. As AI becomes the primary interface to the web, this layer will replace the role of traditional search engines. We are designing how AI agents - not humans - retrieve, evaluate, and reason over web data in real time, under strict latency and reliability constraints. This means solving retrieval and ranking under entirely new access patterns and at significant scale, with systems operating over constantly changing, unstructured data and serving tens of thousands of production workloads 24 by 7. This role comes with ownership over key parts of our applied AI research direction and system design, with a strong expectation of defining new approaches and shipping measurable impact in production.What you'll work on:Designing agent native retrieval systems optimised for machine consumption rather than human search UXBuilding systems where LLMs iteratively plan, query, refine, and reason over resultsDeveloping ranking and retrieval approaches for multi step, agent driven workflows under real world constraintsYour responsibilites:Drive applied research and technical direction across retrieval and ranking systemsDesign and evolve multi stage retrieval architectures (query understanding, rewriting, reranking, iterative retrieval)Develop methods for grounding LLMs in real time web data at scaleDefine and implement new evaluation paradigms and metrics for agentic systems, where correctness is not reducible to clicksLead experimentation on modern retrieval approaches (embeddings, hybrid search, reranking) and bring them into productionAnalyse trade-offs across relevance, latency, and cost at scaleWork closely with engineering to deploy systems in high throughput, low latency environmentsOwn ambiguous problems end to end and contribute to product and research directionMentor engineers and help raise the technical bar of the teamMust haves:8+ years of experience in applied AI, ML, or software engineeringProven track record of shipping ML or AI systems to production at scaleDeep experience with search, retrieval, ranking, recommendation systems, or assistantsStrong understanding of modern deep learning, especially transformers and embeddingsExperience with LLM integrated or knowledge intensive systemsExperience designing evaluation frameworks and metrics for ML systemsStrong programming skills in Python and at least one of Go, C++, or similarAbility to operate in a fast moving, product driven environment with high ownership and autonomyNice to haves:Experience with large scale search or recommendation systemsBackground in agentic AI systems (agents, tool use, autonomous workflows)Experience with RAG, multi step retrieval, or tool usePublications, open source, or similar signals of technical depth and impactBenefits & PerksCompetitive compensationCareer growth and learning opportunitiesFlexibility and ownershipCollaborative and innovative cultureOpportunity to work on impactful AI projectsInternational environment and talented teamsWhat’s it like to work at NebiusFast movingBold thinkingConstant growthMeaningful impactTrust and real ownershipOpportunity to shape the future of AIEqual Opportunity StatementNebius 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…
#J-18808-Ljbffr