Senior Full-Stack Engineer

About Clarion At Clarion, we're rebuilding how healthcare communicates in the age of AI. Today, clinics miss 30-40% of patient calls while staff drowns in administrative tasks. We believe AI agents should handle these workflows—scheduling, billing, prescription refills—so healthcare teams can focus on actual patient care. We're building the communication infrastructure that modern healthcare desperately needs. Our AI agents don't just answer calls; they complete entire workflows end-to-end, giving providers back their time and ensuring patients never go unheard. We've already handled hundreds of thousands of patient interactions across virtual care companies, health systems, and a $5B health insurance company. Founded by a Stanford/Harvard-trained physician who was on the founding team of Two Chairs and Ophelia, and an ex-Amazon Alexa engineer who led AI/ML teams at Salesforce, we uniquely understand both the clinical and technical challenges of transforming healthcare communication. We've raised $5.4M from Accel, Y Combinator, Sequoia (scout), and healthcare founders from Ophelia, Medallion, and Counsel Health. We're an in-person team based in New York, moving fast to ensure no patient call goes unanswered. Why Join Us?

• Early-stage with strong market validation: We have dozens of paying customers with rapidly growing revenue and strong market signals, while offering the high-impact environment of an early-stage startup.
• Solving a massive healthcare challenge: We're addressing a critical problem in healthcare communication that affects millions of patients and providers daily, with technology that can truly transform the patient experience.
• Technical founding team: You'll work directly with experienced founders who deeply understand both healthcare operations and technical development, enabling faster decision-making and better product outcomes.
• Cutting-Edge Tech Frontier: You’ll harness the latest generative AI models—LLMs, voice synthesis, and real-time transcription—to craft conversational agents that transform healthcare communication, while driving innovation to push these technologies beyond their current limits.
• In-person collaboration advantage: We've built in-person since day one and maintain this as a strategic advantage—we move faster, build stronger bonds, and create a cohesive culture.

What you'll be working on

• Lead deployment and optimization of AI agents in live, high-stakes healthcare environments, owning end-to-end performance and reliability.
• Architect and scale full-stack systems that integrate with complex EHRs, legacy healthcare platforms, and real-time voice infrastructure.
• Drive technical strategy for customer-facing solutions, collaborating with product and engineering to translate client needs into scalable architecture.
• Mentor engineers and enforce best practices in code quality, testing, security, and HIPAA-compliant development.
• Shape product roadmap by identifying systemic challenges in customer workflows and proposing high-leverage technical solutions.
• Own critical integrations and troubleshoot production issues across distributed systems under strict uptime and compliance requirements.

Requirements

• Technical leadership: 5+ years of full-stack engineering experience, with a proven track record of designing, building, and scaling production systems in high-reliability environments.
• Full-stack mastery: Expert-level proficiency in our tech stack (Node.js, TypeScript, React, PostgreSQL), with strong system design skills and experience debugging complex, distributed systems.
• High agency and ownership: Thrives in ambiguity, makes high-impact decisions independently, and takes full responsibility for system outcomes and customer success.
• Leadership & communication: Experience mentoring engineers, leading cross-functional initiatives, and translating technical trade-offs to non-technical stakeholders.

You are a good fit if

• You build with intensity and excellence—shipping robust, scalable code fast, solving hard problems end-to-end, and performing under pressure.
• You take full ownership of systems and outcomes, acting decisively in unclear or rapidly evolving situations.
• You bring technical depth, architectural judgment, and a collaborative spirit—driven to solve mission-critical challenges alongside customers and teammates.

Interesting Technical Challenges

• Generative AI at Scale: Design and operate production systems using LLMs with rigorous safety, alignment, and real-time monitoring at enterprise scale.
• AI for Healthcare Conversations: Build voice agents that master medical terminology, navigate multi-step clinical workflows, and achieve decision accuracy on par with trained staff.
• Real-time Voice Infrastructure: Engineer ultra-low-latency systems that process speech in milliseconds, support thousands of concurrent calls, and guarantee 99.99% availability.
• Integration with Fragmented Systems: Create a resilient abstraction layer over diverse healthcare ecosystems—from modern APIs to legacy mainframes—ensuring seamless, secure interoperability.
• Highly Personalized Experiences: Develop adaptive AI that retains patient context across sessions, personalizes tone and flow, and delivers conversations indistinguishable from human care.