Senior Data Scientist - RAG, LLM & Retrieval Systems

Elsevier; Greater London; On-site; GBP 65,000 - 105,000; Full time

Benefits offered by this job

Flexible working hours

Wellbeing initiatives

Shared parental leave

Study assistance

Sabbaticals

Country-specific benefits

Job summary

Elsevier's Search & AI Evaluation team in London/Amsterdam is seeking a senior ML researcher to lead the development and evaluation of scalable lexical, vector, and hybrid retrieval systems, and to architect robust RAG pipelines with optimized retrieval strategies.

You will partner with engineering and domain experts to deliver production-ready AI solutions, design rigorous offline and online evaluation, and advance knowledge graphs, metadata integration, and enterprise-scale discovery across

Qualifications

• Masters or PhD in CS/DS/ML or equivalent practical experience.
• Experience in data science, ML, or applied NLP.
• Hands-on experience with search and retrieval systems (lexical, vector, hybrid).
• Hands-on experience with RAG pipelines and LLM-based systems.
• Strong Python programming skills.
• Experience with PyTorch, Hugging Face, LangChain, LangGraph, or Haystack.
• Experience with Databricks or similar platforms.
• Strong experimentation design and statistical analysis.

Responsibilities

• Lead development and optimization of lexical, vector, and hybrid retrieval systems at scale.
• Architect and improve RAG pipelines, including retrieval strategies and prompt design.
• Drive experimentation with embeddings and ranking models to improve relevance.
• Collaborate with engineering to deploy production-ready implementations.
• Define evaluation strategies for search and GenAI across products.
• Design evaluation frameworks for IR and GenAI (NDCG, recall).
• Contribute to datasets, gold standards, annotation strategies.
• Ensure responsible AI practices including bias and fairness.

Skills

Python

PyTorch

Hugging Face

Databricks

NLP/IR

MLOps

Power BI

Tableau

Education

Master's or PhD in CS/DS/ML

Tools

Databricks

LangChain

LangGraph

Haystack

PyTorch

Job description

Elsevier's Search & AI Evaluation team in London/Amsterdam is seeking a senior ML researcher to lead the development and evaluation of scalable lexical, vector, and hybrid retrieval systems, and to architect robust RAG pipelines with optimized retrieval strategies.

You will partner with engineering and domain experts to deliver production-ready AI solutions, design rigorous offline and online evaluation, and advance knowledge graphs, metadata integration, and enterprise-scale discovery across