JR-186652 Full stack Developer Senior

Job Description: We are seeking a Senior Full Stack Engineer (.NET / React) to join a US-based healthcare client in the oncology domain. You will contribute to the maintenance, modernization, and continuous evolution of an Electronic Health Record (EHR) platform used in cancer treatment practices. The system manages sensitive patient and clinical data, including medical history, lab results, treatment plans, allergies, and appointment scheduling, requiring strong attention to performance, scalability, and data integrity. This is a full-stack role with an expected split of approximately 60% backend (.NET) and 40% frontend (React), depending on project needs. You will work across both legacy and modern components, delivering new features while supporting system improvements, and collaborating closely with cross-functional teams in an agile environment to ensure a reliable and secure healthcare solution. Locations: Brazil Colombia Argentina Peru Uruguay Costa Rica Mexico  Requirements:  Must-Have Skills: Strong experience in .NET (C#) development; Familiarity with ASPX Web Forms or willingness to learn quickly; Professional experience with React.js in a production environment; Solid working knowledge of SQL and relational databases; Experience using Git for version control. Nice-to-Have Skills: Experience with Python for basic scripting and small updates; Ability to navigate the AWS Console for basic debugging and log review; Familiarity with React Native and Apple App Store deployments; Exposure to monitoring tools like Splunk or Datadog; Open to working with and improving legacy codebases; Willing to gradually contribute to modernization initiatives.  Job Responsibilities:  Develop and maintain features in a .NET (C#)-based application; Work with legacy ASPX Web Forms and participate in their gradual migration to React; Handle tickets independently based on Jira tasks; Write, debug, and optimize SQL queries; Occasionally make small updates or bug fixes in Python (rare); Use the AWS Console to troubleshoot errors, review logs, and verify service statuses; Collaborate with a generalist team on end-to-end solutions spanning frontend and backend; Participate in a rotating on-call schedule (approx. every 5 weeks, mostly during U.S. business hours); Optional: assist with maintenance tasks for a React Native iOS app (small, infrequent updates). What We Offer: Competitive salary; 100% remote opportunity; Paid time off (PTO), sick leave, and national holidays. Benefits will be communicated during the application process depending on your location; Travel expenses are covered when applicable; Referral program; Paid certification program; Personal development plan (PDP); Access to the language platform. Job ID: JR-186652