Senior Application Security Engineer

At Counterpart Health, we are transforming healthcare and improving patient care with our innovative primary care tool, Counterpart Assistant. By supporting Primary Care Physicians (PCPs), we are able to deliver improved outcomes to our patients at a lower cost through early diagnosis and longitudinal care management of chronic conditions. We are looking for a Senior Application Security Engineer to break Counterpart Assistant before anyone else does. This is a hands-on offensive security role on our Eng Core team, the group responsible for foundational work across the platform. You will hunt for vulnerabilities in software that thousands of practitioners use during live patient visits, close the gaps you find, and raise the security floor of every engineer around you. As a Senior Application Security Engineer, you will: Actively hunt for and close security vulnerabilities across our core product, Counterpart Assistant. You will use a variety of different tools and scripts you write yourself to map a real attack. Harden the systems, services, and endpoints around the platform. Establish strong security monitoring of our services and stack. Safeguard PHI and monitor deidentification practices. Find the paths where protected data could leak and close them. Use AI as a force multiplier for finding gaps; using agents and frameworks that scale vulnerability discovery, with guardrails you set. You will also help the engineering org build safely as the threat landscape around AI keeps moving. Raise the bar for others. Review critical pull requests across every team, run security training, and mentor engineers whose secure coding needs work. Partner with site reliability engineering, engineering leadership, and corporate security teams to establish defensive strategies to safeguard our data. Strengthen our resilience and ensure disaster recovery is strong. You should get in touch if: You have 8+ years in software engineering and 4+ years focused on application security, vul