Senior Machine Learning Engineer, Platform

Our Story   Since 2023, our mission has been clear: to be the north star of patient equity.   Every day, we strive to bridge the gaps in healthcare access and outcomes to ensure that every patient, regardless of background or circumstance, receives the care they deserve. As a member of our team, you'll be at the forefront of innovation, working alongside passionate individuals who share your dedication to creating best-in-class, patient-centric products in healthcare. Together, we're revolutionizing the way people understand their health and working with the world's top researchers to accelerate innovation. About Novellia Novellia is the first and only company that lets anyone in the U.S. gain access to nearly a decade of their health data in under 30 seconds — 100% free. All your health records, across every doctor, in one place, always up to date. We are the only patient-powered real-world data platform delivering comprehensive, patient-authorized longitudinal health insights to accelerate biopharma innovation. Unlike traditional RWD providers who deliver fragmented institutional data, we empower patients to access 20+ years of their health records, then transform these complete health journeys into fit-for-purpose datasets for evidence generation, regulatory submissions, and market access. We are growing 5x year over year, have raised close to $30M in funding, and are backed by tier-1 investors including Spark Capital, Khosla Ventures, and Bling Capital. Working with the world's top researchers, we turn health insights into life-changing action for millions of people around the world.

Most of what matters in a health record isn't in a structured field - it's in the note, the discharge summary, the pathology report, the scanned fax. Turning that unstructured clinical text into trustworthy, structured features is what makes a longitudinal health history usable for research, and it's one of the highest-leverage capabilities Novellia can own. You'll be our first ML hire, joining Platform Engineering and reporting to the Head of Platform Engineering, as technical owner of this multi-quarter effort. The interesting decisions are still open - what we extract first, how we know we're right, what a mature extraction pipeline looks like at our scale. There's no existing approach to inherit or defend. The work draws on two toolkits. Roughly 70% is applied ML on clinical text: entity extraction, classification, sequence labelling, annotation strategy, error analysis, calibration, and the evaluation discipline that tells you whether your numbers mean anything. Roughly 30% is LLM-based: prompt development, structured output, retrieval, and the evals and observability that keep generative approaches honest. Deciding which approach a given problem calls for is the most interesting part of the job, and that call is yours. We're looking for a leader in this seat: setting technical direction rather than waiting to be handed a problem. If this grows the way we think it will, leading the team we build around it is on the table.

Own the full lifecycle of extraction models - framing, data/annotation strategy, model selection, training/fine-tuning, evaluation, deployment, monitoring, retraining. Not a research seat, not a hand-off seat. Define what "accurate enough" means with clinical and customer-facing stakeholders, and build the evaluation harness that makes the answer defensible - the first deliverable, not a follow-up. Partner with Clinical Data Managers on curation design and own the technical half of QA/QC alongside them: which variables are extractable, how an instruction becomes a model spec, and the tooling/sampling/error analysis behind human-in-the-loop review. Build clinical NLP pipelines against messy real-world data and work with backend engineers to productionize what you build. Use LLMs with the same rigor you'd apply anywhere: versioned prompts, real evals, tracked cost/latency, known failure