Post-doctoral research opportunity in applied biomedical terminology and classification development and deployment for translational research purposes. The emphasis will be on the continued development and testing of a clinical value-set server, targeted to the National COVID Cohort Collaborative (N3C), its non-COVID successor, and the larger OMOP observational research communities. Applications include controlled medical vocabularies and the management of clinical terminology code sets used in phenotyping and cohort selection algorithms. The environment entails full-stack software development with JavaScript, React, Python, PostgreSQL, and semantic graph analysis and visualization tools. Opportunities to contribute to ICD11 infrastructure, as well as a funded LOINC revision process to enhance ontological capacity are also available. Participation in or leadership on manuscripts about these projects is expected. This is an NIH training grant funded opportunity, so applicants must qualify as US citizens or be Permanent Resident (Green) Card holders. Interested persons should attach their CV and contact: Christopher Chute, MD DrPH; Chief Research Information Officer, Johns Hopkins Medicine. chute@jhu.edu