Company Overview:
Function Health is the AI operating system for health, designed to empower people to live 100 healthy years. We are redefining how individuals understand, measure, and improve their health by moving beyond the limitations of traditional care and enabling comprehensive, continuous insight into human biology. Function has been recognized as one of Fast Company’s Most Innovative Companies of 2024, and is venture-backed by Redpoint and other leading venture firms. Over half a million members have joined Function to take control of their health.
Through comprehensive lab testing, MRI and CT imaging, longitudinal data, and guidance from AI and clinical teams, Function gives members a complete and continuous view of their health — and the clarity to act on it. Through acquisitions across imaging, mobile phlebotomy, and supplement tracking and optimization, Function is building an integrated health platform that spans the full path from testing to health clarity to daily action.
Function recently announced a $298M Series B and is entering its next chapter of growth. As we scale, the quality and durability of our People systems, data, and insights will directly shape our ability to attract, retain, and support exceptional talent.
We are growing our team and seeking out world-class talent that deeply believes in our mission to positively impact global health, has a relentless bias toward action, and a growth mindset. Function fosters a collaborative and dynamic environment where every day we build the future.
Role:
We sit on something rare: a fast-growing longitudinal health dataset spanning 50M+ lab tests, 160+ biomarkers per member, advanced imaging, and wearable signals, captured continuously rather than once a year at a checkup.
You'll own the agentic system that turns a member's health data into clear next steps, working alongside their clinicians. Day to day, that means building and operating production multi-agent systems end to end: orchestration graphs, tool use and memory, retrieval over a member's records, and the evals and observability to keep it reliable. You'll wire frontier LLMs into Function's proprietary data, and hold the whole thing to the safety, latency, and cost controls healthcare demands.
This is a hands-on, high-ownership role for an engineer who has built agents at scale and wants their work measured in healthy years of human life, not just benchmarks.
Impact You'll Drive:
- Put a concierge doctor in every member's pocket: an agent that reasons over a lifetime of labs, imaging, and wearable signals and tells them what to do next.
- Turn our longitudinal health dataset into decisions, not dashboards, so members act on their health rather than just view it.
- Make health AI that people trust with their lives: every recommendation earns its way past evaluation gates and clinician review before it reaches a member.
- Catch what a once-a-year physical misses, surfacing the early signal across 160+ biomarkers before it becomes a diagnosis.
Key Responsibilities:
- Architect and build stateful, graph-based agent workflows with tool use, planning, and memory.
- Integrate LLMs and multimodal models via structured I/O (JSON Schema, Pydantic validators) and function/tool calling.
- Build high-reliability APIs and streaming services for real-time inference, speech, and vision.
- Own production readiness: tracing, logging, metrics, rate limiting, circuit breakers, and SLOs
- Stand up eval pipelines: offline golden sets, LLM-as-judge with human rubrics, online A/B, and regression tests in CI.
- Implement retrieval and memory: hybrid search, vector and graph retrieval, semantic caches, and long-horizon context.
- Optimize cost/latency: model routing, prompt and tool selection, quantization, and KV cache/prefill strategies.
- Partner cross-functionally to translate research into robust production systems and iterate quickly behind evaluation gates.
- Mentor engineers through design docs and architecture decisions.
Qualifications/Skills:
To excel in this role, candidates must bring a unique combination of skills and experiences:
- 1+ years building agentic AI systems; 6+ years as a full-stack or ML engineer, building production backends or ML systems in Python, Go, or similar.
- Fluency with agentic orchestration (e.g., LangGraph, PydanticAI, DSPy, LlamaIndex) and tool/function calling.
- Experience integrating frontier LLMs and multimodal models via managed APIs or self-hosted serving.
- Strong with API design and backend frameworks (FastAPI, Flask) and event-driven architectures.
- Data systems expertise with PostgreSQL, including token streaming and throughput tuning.
- Retrieval and memory: vector databases (pgvector, Pinecone, Weaviate, Milvus), hybrid search, and graph/knowledge storage.
- Production evals: LLM-as-judge, human-in-the-loop, rubric design, and CI-integrated regression tests.
- Observability and SRE: OpenTelemetry traces, metrics, structured logs, SLOs, dashboards, and on-call triage.
- Cloud-native delivery: Kubernetes, Terraform, Docker, GPU scheduling/autoscaling on AWS or GCP.
- CI/CD proficiency with GitHub Actions and test automation for prompts, tools, and agents.
- Clear, concise communication and high ownership in fast-paced environments.
Nice to Haves:
- Real-time multimodal systems: streaming ASR, low-latency TTS, WebRTC, and vision pipelines.
- RAG expertise beyond basics: Graph RAG, multi-hop retrieval, sub-agents, query planning, and freshness policies.
- Safety and governance: policy-as-code, red-teaming, PII handling, audit logs, and role-based tool authorization.
- Regulated data experience (HIPAA, SOC 2, GDPR) and data residency controls.
- Personalization at inference time, long-term memory agents, session state, and episodic memory stores.
- Experience with consumer-scale AI apps, high-traffic systems, or on-device/edge acceleration (WebGPU).
To be a strong fit, you also need:
- Ruthless Prioritization:
- We don’t let perfect get in the way of progress.
- We move quickly to drive value, not perfection.
- We prioritize what drives impact.
- We never compromise on standards of excellence.
- Member-First, Always:
- We design and deliver like we’re caring for someone we love.
- We create calendar, actionable, human experience.
- We prioritize responsiveness, peace of mind, and outcomes.
- We empower members with truth, clarity, and care.
- One Team, Moving Fast:
- We are aligned in purpose, prioritization, and speed.
- We gather diverse perspectives to make informed decisions.
- We clear paths for each other and move fast together.
- We communicate clearly and respectfully, rallying around shared goals.
- Radical Ownership, Relentless Execution:
- We don’t just ship– we own outcomes and drive results.
- We act with urgency and precision
- We anticipate, initiate, and follow through.
- We meet challenges with grit and pragmatism.
- We embrace new tech to deliver better outcomes.
- Mission Over Ego:
- We are ruthlessly aligned to our mission - and leave ego at the door.
- We disagree and commit.
- We don't tolerate politics or withholding information.
- We operate with honesty, transparency, and respect.
- Sustained Integrity in Every Detail:
- We earn trust by obsessing over accuracy, quality, and clarity in everything we do.
- We prioritize clinical precision - data must be right.
- We sweat the details because outcomes depend on them.
Your dedication to these responsibilities will directly contribute to the success of our platform and the satisfaction of our users. We are looking for a proactive, skilled, and forward-thinking individual to join our team and help shape the future of our services.
Why You'll Love Working With Us:
We value our team at Function and offer a competitive salary and benefits package, flexible working hours, and a dynamic work environment where creativity and innovation are encouraged. If you are a highly motivated and experienced individual who is passionate about using technology to improve people’s lives, we would love to hear from you.
At Function, we celebrate diversity and are committed to building a diverse and inclusive workforce. As an equal opportunity employer, we do not discriminate on the basis of race, color, gender identity, ancestry, religion, age, sexual orientation, national origin, disability, marital status, Veteran status, or any other occupationally irrelevant criteria.
Join the Function Health team and become a part of our mission to build a healthier future for all. Discover more about us and how we're changing the face of healthcare at Function Health.
Important Notice: Legitimate communication from the Function Health team will always come from an email address ending in @functionhealth.com. Function Health will never request personal information such as banking details or payment during the hiring process. Please be cautious of communications or job offers that come from other email domains, instant messaging platforms, or unsolicited calls. If you ever have doubts about the legitimacy of a communication, please reach out to us directly at [email protected].