Senior Applied Scientist, Search & Information Retrieval

Role Description

This is an applied science position focused on building and deploying production-grade search systems that power Westlaw, PracticalLaw, and CoCounsel. You will work across neural information retrieval, semantic and hybrid search, re-ranking, and query understanding — delivering search quality and relevance at scale for legal and professional content.

Qualifications

• PhD or Master's in Computer Science, AI, NLP, or a related field
• 5+ years of post-degree industry experience shipping search, retrieval, or RAG systems into production — not research-only experience
• Publications at SIGIR, ECIR, NeurIPS, ACL, EMNLP, ICLR, or equivalent
• Production Python and experience with PyTorch, DeepSpeed, Torchtune, or LlamaFactory
• Hands-on production depth required in:
  • Neural IR fundamentals: BM25, hybrid search, dense retrieval (DPR, ColBERT), bi-encoders, cross-encoders, late interaction models
  • Search and RAG system design: vector databases, retrieval strategies, document chunking, metadata filtering, re-ranking, context optimisation, and orchestration
  • Evaluation framework design for retrieval quality at component and system level
  • Post-training of large language models and their application to retrieval systems
  • Deep learning and NLP fundamentals

Requirements

• Design, build, and deploy end-to-end neural search systems including dense retrieval, hybrid search, semantic chunking, embedding models, cross-encoders, SLM re-rankers, and transformer-based approaches
• Develop models for query understanding, document re-ranking, and retrieval quality optimization
• Build evaluation frameworks — component-level and end-to-end — using expert annotation and synthetic data generation
• Drive independent technical decisions on retrieval architecture, indexing strategy, ranking models, and evaluation methodology
• Partner with engineering on delivery, reliability, and scale across multiple product lines
• Contribute to published research at venues such as SIGIR, ECIR, NeurIPS, ACL, EMNLP, and ICLR, and to intellectual property

Benefits

• Flexibility & Work-Life Balance: Supportive workplace policies designed to help manage personal and professional responsibilities, including work from anywhere for up to 8 weeks per year.
• Career Development and Growth: Culture of continuous learning and skill development with tools and knowledge to grow, lead, and thrive in an AI-enabled future.
• Industry Competitive Benefits: Comprehensive benefit plans including flexible vacation, mental health days, retirement savings, tuition reimbursement, and resources for wellbeing.
• Culture: Award-winning reputation for inclusion and belonging, flexibility, and work-life balance.
• Social Impact: Opportunities for community involvement with paid volunteer days and pro-bono consulting projects.
• Making a Real-World Impact: Helping customers pursue justice, truth, and transparency.