Senior Software Engineer-Backend

THE OPPORTUNITY As a Senior Software Backend Engineer at Hinge Health, you will play a key role in designing, building, and maintaining scalable software solutions that directly improve member health outcomes. You will work closely with cross-functional partners, including product managers, designers, and fellow engineers, to deliver new capabilities and enhance the maintainability, reliability, and performance of our products. In this role, you will help advance Hinge Health’s mission to transform joint and muscle care through technology. This includes contributing to AI-driven solutions that automate workflows, improve care delivery, and create better experiences for both care teams and members. Hinge Health engineers work in small, interdisciplinary teams aligned to different parts of the member journey, with strong ownership from development through production. You will join the CareHub team, which is building the platform where care happens at Hinge Health. CareHub is the unified system that equips physical therapists, health coaches, care managers, and other care teams with the tools they need to deliver personalized, high-quality musculoskeletal care. It brings together member history, care plans, documentation, communication, and daily workflows in one place, enabling clinicians to spend less time navigating systems and more time supporting members. As CareHub 2.0 evolves, the team is modernizing the platform to improve performance, scalability, and user experience, while also introducing AI-powered capabilities that simplify workflows and increase operational efficiency across care delivery. We operate in a continuous deployment DevOps culture and take owner-operator pride in supporting our code in production. Our production systems use technologies including React Native, React, Node.js, TypeScript, NestJS, GraphQL, Docker, Rails, AWS, Postgres, Redis, Apollo, and Redux. Our engineering workflow follows trunk-based CI/CD, and our security and compliance standards meet the demands of healthcare, including HIPAA, HITRUST, SOC 2, and CCPA. WHAT YOU'LL ACCOMPLISH - Deliver large projects that introduce new product capabilities, often acting as a maintainer for key code repositories. - Break down complex problems into manageable tasks, ensuring steady and predictable delivery while identifying and resolving root causes of incidents. - Collaborate with your team to roadmap and execute ambitious technical strategies, balancing short-term and long-term trade-offs. - Mentor and support junior engineers, providing thoughtful code reviews and real-time pairing. - Design and build AI-powered clinical agents using LangGraph.js for stateful orchestration, composing multi-node StateGraphs that handle context gathering, LLM reasoning, and action execution within a shared NestJS service. - Integrate LangSmith for end-to-end AI observability, including prompt versioning and management via LangSmith Hub, automated per-node tracing, evaluation pipelines with golden datasets, and CI-gated quality checks that block regressions before merge. - Develop and maintain agentic workflows that leverage LLMs (Claude Sonnet via AWS Bedrock) - Contribute to the Member-Centric Knowledge Graph and RAG-based retrieval systems that give agents the clinical context, causal evidence, and relationship awareness needed for intelligent decision-making. - Proactively improve the maintainability, availability, and performance of the team's features, and contribute to the team's overall architecture and developer tooling. - Communicate technical ideas clearly to both technical and non-technical partners, and document solutions for future reference. WHO YOU ARE - A "Learn-it-all": You are proficient in modern stacks (TypeScript, Node.js) but remain curious. You leverage AI tools to accelerate your workflow and are eager to explore new technologies to solve complex problems. - A Trust Builder: You communicate complex technical ideas clearly to both technical and…