Principal AI Researcher - Agentic Retrieval at Scale

Nebius B.V.; Amsterdam; Hybrid; EUR 140,000 - 190,000; Full time

Job summary

Nebius B.V. is seeking a Staff or Principal Applied AI Researcher to advance an agent native search platform in Amsterdam. You will own retrieval architectures, improve grounding of LLMs, and push production-ready AI systems with low latency.

You will design multi-stage retrieval, collaborate with engineers, and mentor team members while targeting measurable impact and scalable AI tooling.

Qualifications

• 8+ years of experience in applied AI, ML, or software engineering.
• Proven track record of shipping ML or AI systems to production at scale.
• Deep experience with search, retrieval, ranking, recommendation systems, or assistants.
• Strong understanding of modern deep learning, especially transformers and embeddings.
• Experience with LLM integrated or knowledge intensive systems.
• Experience designing evaluation frameworks and metrics for ML systems.
• Strong programming skills in Python and at least one of Go, C++, or similar.
• Ability to operate in a fast moving, product driven environment with high ownership and autonomy.

Responsibilities

• Drive applied research and technical direction across retrieval and ranking systems.
• Design and evolve multi stage retrieval architectures (query understanding, rewriting, reranking, iterative retrieval).
• Develop methods for grounding LLMs in real time web data at scale.
• Define and implement new evaluation paradigms and metrics for agentic systems, where correctness is not reducible to clicks.
• Lead experimentation on modern retrieval approaches (embeddings, hybrid search, reranking) and bring them into production.
• Analyse trade-offs across relevance, latency, and cost at scale.
• Work closely with engineering to deploy systems in high throughput, low latency environments.
• Own ambiguous problems end to end and contribute to product and research direction.
• Mentor engineers and help raise the technical bar of the team.

Skills

Applied AI

ML systems

Search systems

Transformers

Embeddings

Python

Go/C++

Tools

Python

Go

C++

Job description

Nebius B.V. is seeking a Staff or Principal Applied AI Researcher to advance an agent native search platform in Amsterdam. You will own retrieval architectures, improve grounding of LLMs, and push production-ready AI systems with low latency.

You will design multi-stage retrieval, collaborate with engineers, and mentor team members while targeting measurable impact and scalable AI tooling.