Software Engineer III — Full Stack (Backend-Focused, Core Platform Services)

McKesson is an impact-driven, Fortune 10 company that touches virtually every aspect of healthcare. We are known for delivering insights, products, and services that make quality care more accessible and affordable. Here, we focus on the health, happiness, and well-being of you and those we serve – we care. What you do at McKesson matters. We foster a culture where you can grow, make an impact, and are empowered to bring new ideas. Together, we thrive as we shape the future of health for patients, our communities, and our people. If you want to be part of tomorrow’s health today, we want to hear from you. Role Summary Ontada's Engineering team builds iKnowMed (iKM), the leading Oncology EMR platform used by thousands of clinicians across the US to manage cancer treatment — from regimen ordering and chemotherapy scheduling to genomic result interpretation and clinical trial matching. We are hiring a Software Engineer III (P3) to design and build well-scoped core services, shared frameworks, and platform components that domain teams depend on to deliver clinical applications. This is a backend-first full-stack role — you will spend the majority of your time in Java and Spring Boot building services, APIs, and event-driven integrations, with frontend work focused on building integration layers, enablement UIs, and end-to-end validation using React and TypeScript. You will wor [... source excerpt omitted ...] dards: HL7v2, FHIR, C-CDA, SNOMED CT, LOINC, RxNorm Quality: JUnit, Mockito, Integration Testing, Code Reviews Documentation: Markdown, Mermaid diagrams, API specifications Key Responsibilities Backend Services and API Development Design and implement well-scoped backend services and shared components using Java and Spring Boot, following established architectural patterns Build and maintain RESTful APIs with clear contracts, consistent error handling, and comprehensive documentation that domain teams can adopt with minimal friction Implement event-driven integrations using Kafka — produce and consume events that connect clinical workflows across services (e.g., order state cha [... source excerpt omitted ...] result notifications, patient data sync) Build data integrations and pipeline components that connect to Databricks for analytics, reporting, and clinical data processing Write production-quality code against Oracle databases using JPA/Hibernate, with attention to query performance, transaction management, and data integrity Core Platform Enablement Contribute to common core services, shared libraries, and frameworks that are consumed by multiple clinical domain teams (ordering, scheduling, clinical documents, genomics) Build services with reusability as a first-class requirement — consistent API patterns, well-defined event schemas, clear extension points Collaborate with d