Principal Applied AI Researcher - Agentic Search Leader

Nebius Group; Zurich (KS); On-site; USD 180,000 - 280,000; Full time

Benefits offered by this job

Competitive compensation

Career growth and learning

Flexibility and ownership

Collaborative and innovative culture

Impactful AI projects

International environment

Job summary

Nebius is seeking a Staff or Principal Applied AI Researcher to join a fast-growing team building an agent-native search platform. You will own critical parts of applied AI research and system design, delivering measurable impact in production at scale.

The role focuses on retrieval, ranking, and grounding LLMs in real-time web data, with emphasis on latency, reliability, and cost. You’ll lead exploration and mentor engineers in a dynamic, impactful environment.

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, 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.
• Lead experimentation on modern retrieval approaches (embeddings, hybrid search, reranking).
• 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

Software engineering

Python

Go/C++

System design

Tools

Go

C++

Python

Job description

Nebius is seeking a Staff or Principal Applied AI Researcher to join a fast-growing team building an agent-native search platform. You will own critical parts of applied AI research and system design, delivering measurable impact in production at scale.

The role focuses on retrieval, ranking, and grounding LLMs in real-time web data, with emphasis on latency, reliability, and cost. You’ll lead exploration and mentor engineers in a dynamic, impactful environment.