AI Engineer

New York, NY · Full-time · Hybrid (in office 3 days a week) · $150,000 - $275,000 + equity

We’re deploying advanced agents into the real world to solve some of the biggest pain points in healthcare, and bringing the JOY back to healthcare by fixing the financial chaos behind it.

Every year, healthcare practices fail to collect an estimated $125 billion in earned revenue. The money disappears into fragmented financial data, manual workflows, and opaque payer systems that don’t talk to one another. Often, these costs are passed on to patients through higher bills or rising health costs, and for many practices the losses are fatal.

Joyful Health builds AI agents that take on insurers so providers get paid for the care they deliver. We didn’t start with a product. We spent ten months working as fractional CFOs for a dozen practices, doing the work alongside providers before we wrote the technology that automates it.

We just announced our $22M Series A, led by CRV, with world-class investors including the founders of MongoDB and KAYAK. Now we’re doubling our engineering team.

We’re looking for a talented and ambitious AI Engineer with 4+ years of experience building production AI systems who’s excited to solve one of the toughest challenges in healthcare: automatically resolving claim denials. You’ll be the technical lead for our agentic AI platform that autonomously researches, understands, and resolves insurance claim denials, helping healthcare practices recover millions in lost revenue.

Resolving denials requires deep expertise in medical billing, payer rules, and claim documentation. Today, billing managers spend hours manually researching each denial, gathering supporting documentation, and crafting appeals. We’re building an agentic AI system that automates this entire workflow, from denial classification and root cause analysis to evidence gathering and appeal letter generation.

You’ll architect and build the intelligent agents that power this system. You’ll design multi-agent workflows that collaborate to interpret complex denial reasons, retrieve relevant clinical and billing information through RAG systems, reason about payer policies, and generate compelling appeals. This is a greenfield opportunity to build a production agentic system that directly impacts the financial health of healthcare practices.

You should be comfortable (and excited!) working in a fast-paced, early-stage startup environment where you’ll wear many hats and take on new challenges as they arise. This is a great opportunity for someone who wants to work on something extremely challenging at the intersection of AI and healthcare.

• Design and build the architecture for our agentic AI system that autonomously resolves insurance claim denials.

• Develop specialized AI agents for denial classification, root cause analysis, evidence retrieval, policy reasoning, and appeal generation.

• Implement multi-agent orchestration frameworks that coordinate complex workflows across research, decision-making, and document generation.

• Build and optimize RAG systems to retrieve relevant clinical documentation, billing records, and payer policy information.

• Create evaluation frameworks and feedback loops to continuously improve agent performance and reliability.

• Design prompt engineering strategies and fine-tuning approaches to optimize LLM behavior for healthcare billing workflows.

• Work closely with billing managers to understand denial resolution workflows and translate them into agent behaviors.

• Collaborate with the engineering team on production infrastructure for deploying and monitoring AI agents at scale.

• Actively contribute to building the team’s AI/ML vision and technical roadmap.

• Collaborate on code reviews and technical design documents to ensure code quality and distribute knowledge.

• You’re passionate about Joyful Health’s mission. You want to solve real, pressing problems for providers and put them in control of their businesses. You naturally empathize with users and enjoy building with their needs in mind.

• You have 4+ years of experience in machine learning or AI engineering, with a focus on building production AI systems and deploying models at scale.

• You have strong technical execution. You view coding as a craft, not just a task, and you care about building a product that works at scale, with the user at the forefront. You’re proficient in:

  • Python and modern ML frameworks (PyTorch, TensorFlow, or JAX)

  • LLM technologies, including prompt engineering, fine-tuning, and RAG systems

  • Vector databases and semantic search systems

  • Building reliable, production-grade AI systems with proper evaluation and monitoring

  • MLOps practices, including model versioning, A/B testing, and performance tracking

  • Working with APIs and integrating AI systems into broader product workflows

• You have a radical sense of ownership. You have the ability and desire to own technical roadmaps and refine ambiguous problems.

• You have a low ego and a growth mindset, and you’re excited to shape our engineering team and culture as an early team member, leading by example and growing your impact as the product and team scale.

• We care more about your drive, hustle, and passion than a college degree from a shiny institution or experience at name-brand companies.

Bonus points

• You have experience working with healthcare data or an understanding of medical billing workflows.

• You’ve been a founder or an early engineer at a startup.

🚀 Meaningful impact. You’ll work on one of the most hair-on-fire problems providers face, so they can focus on caring for patients.

🔑 Autonomy and ownership. As an early team member, you’ll shape the company from the ground up.

📈 Growth and learning. You’ll get direct access to experienced founders and advisors, plus stipends for professional development courses and books.

💰 Competitive compensation and equity. $150K - $275K base, plus strong equity in Joyful Health.

❤️ Be your best self. Comprehensive healthcare benefits, unlimited PTO (with a minimum of 10 days off a year), flexibility, and regular team off-sites and events.

Please apply even if you don’t meet 100% of the criteria. Nobody checks every box every time, and we’d love to talk with you about how you see yourself growing into this role. We’re also very open to candidates with non-traditional experience.

Joyful Health is an equal opportunity employer. We do not discriminate on the basis of race, color, religion, sex, sexual orientation, gender identity, national origin, age, disability, veteran status, or any other legally protected characteristic.