AI Research Scientist (Europe/UK - Remote) at Sword Health

Sword Health operates as both a clinical-centric frontier AI lab and an applied AI platform. The AI Research team builds the core intelligence behind Dawn and Phoenix, their continuous, always-on care agent. Posted: March 25, 2026 Type: Full-time, Hybrid Location: Europe/UK Remote (preference for London or Lisbon/Porto) Salary: EUR 71,000 - 110,000 annually (base, variable, equity) Visa: Requires valid EU visa; no relocation assistance Healthcare demands AI that goes far beyond answering questions or completing tasks. It requires systems capable of sustained engagement across dozens of interactions, understanding a patient's history, perceiving their present state, and guiding their recovery over weeks and months. To make this possible, they are pushing the boundaries of memory systems, multimodal perception (video, audio, wearable signals), and multi-turn reinforcement learning for long-horizon treatment planning. Key Responsibilities: - Design and execute research on LLM fine-tuning, alignment, and post-training techniques (SFT, RLHF) - Develop foundational AI models spanning language, vision, speech, and multimodal systems - Manage the complete model lifecycle: dataset curation, architecture design, training, evaluation - Translate research breakthroughs into production systems serving patient care - Work towards long-term ambitious research goals such as clinical memory, long-horizon planning, and safety validation, while identifying and delivering immediate milestones - Advance the field by publishing in top-tier AI venues and clinical journals - Build research involving sparse rewards, multi-turn conversations, and complex context management Required Qualifications: - PhD in Computer Science, Machine Learning, NLP, or related AI field - Hands-on experience fine-tuning large language models - Strong publication record in peer-reviewed AI venues - Python proficiency and expertise with PyTorch or JAX - Ability to design rigorous experiments and interpret results Preferred Qualifications: - First-author publications at NeurIPS, ICML, ICLR, ACL, EMNLP, or similar venues - Deep expertise in LLMs, reinforcement learning, multimodal learning, or agentic AI - Experience building LLM-based agents including prompt engineering, memory orchestration, or agentic workflows - Track record taking research concepts to working systems - Industry research experience Benefits (Portugal): - Health, dental, vision insurance - Meal allowance - Equity - Remote work allowance - Flexible hours - Discretionary vacation - English classes