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.