---
title: 'AI engineer at Lucis'
canonical: 'https://feeny.ai/job/ai-engineer-lucis-paris-acp2wmr34xyv'
type: 'job'
last_seen: '2026-09-08'
---

# AI engineer at Lucis

- **Company:** Lucis
- **Location:** Paris, France
- **Employment:** full-time
- **Work type:** hybrid
- **Posted:** 2026-04-08
- **Last confirmed live:** 2026-09-08
- **Apply:** https://jobs.ashbyhq.com/lucis/8801f28f-e0ba-4370-8c31-075c881e190a

## Job description

Making preventive health the default for every human in Europe

The mission

At Lucis https://lucis.life/?utm_source=career_job_desc&utm_medium=content, we believe healthcare should be preventive, not reactive. We’re building the OS for human longevity to help people add more healthy years to their lives. You can read more about who we are and how we work here https://lucis.life/careers?utm_source=career_job_desc&utm_medium=content.

## THE ROLE

We're building AI agents that act as a doctor for preventive health — analyzing 110+ biomarkers, reasoning over clinical data, and delivering protocols that change how people age. The system works. Now we need to make it smarter, faster, and ready for millions of users.

As our AI Engineer, you own the reasoning engine: the agents, the retrieval pipelines, the clinical workflows, and the infrastructure that makes it all reliable in production. You work directly with our medical team to translate clinical knowledge into systems that actually behave like they understand it.

This isn't a research role. It's a build role. The gap between a great LLM demo and a trustworthy AI doctor is enormous — your job is to close it.

You could be responsible for

- AI agent architecture — design and ship the multi-agent system behind our AI doctor: reasoning, planning, tool use, clinical citation, and safe fallback behavior
- Retrieval & knowledge — vector infrastructure, embedding pipelines, RAG architecture over clinical literature and user health data. You know the difference between retrieval that works and retrieval that a clinician would trust
- Data pipelines — ingestion and normalization from labs (Eurofins, Randox), wearables, and third-party partners. Clean data in, reliable inference out
- Production reliability — LLM endpoints that reason correctly at scale, with observability, evals, and failure modes you've thought through before they happen
- Medical collaboration — translate complex clinical requirements into agent workflows, working side by side with our medical advisors. You don't need to be a doctor, but you need to earn their trust

## ABOUT YOU

You’re passionate about the future of human health and want your work to help people stay healthy for longer. You move quickly from idea to execution, take full ownership of what you build, and work best with talented people who care as much as you do.

You thrive in fast‑moving environments, learn by doing, and value feedback as a way to continuously improve.

You’ll fit in well if

- You have 8+ years' experience building and shipping software and ML systems in production
- You've shipped AI agents in production recently — not as a side project, as the core product
- You think in systems: prompts, retrieval, tool orchestration, evals, and failure modes are all part of the same design problem
- You're hands-on with vector databases, retrieval pipelines, and LLM endpoints — Python-native, comfortable in LangChain or equivalent
- You write evals before you ship, because you know that vibes-based QA doesn't work for clinical reasoning
- You've worked with messy real-world data (health, finance, legal) and built pipelines that handle it without breaking silently
- You're genuinely obsessed with health — you track your own biomarkers, read PubMed, or are just deeply frustrated that healthcare is still reactive

We might not be a fit if

- You need a clearly defined role with stable responsibilities.
- You prefer strategic advisory work over hands-on execution.
- You've only worked in large, well-established companies.
- You need perfect information before making decisions.
- You prioritise predictable 9–5 work over mission intensity.
- You're uncomfortable with frequent context-switching and urgent pivots.

Our current stack

Python repo and TS monorepo (platform) · PostgreSQL + Prisma · AWS (Terraform) · GitHub Actions · Claude Code + Cursor · AI/agent framework: mostly Langchain ecosystem

## THE PROCESS

- Intro call (20 min): culture & role fit.
- Technical interview (30 min)
- At-home case study: hands-on project, delivery in 2 days.
- Deep dive (90 min) and team chat (on-site)
- Reference calls

## HOW WE WORK

We work together from our Paris hub. We’re passionate about what we’re building and believe the fastest way to create something exceptional is side by side. We’re open to relocation support for the right individuals, and we welcome missionaries who travel to work with us in Paris on a regular basis.

- Rigor without ego: Audits, science, and code all deserve the same high bar.
- Radical ownership: Feedback loops are short; everyone contributes to building the best version of Lucis.
- Velocity over perfection: We ship daily and prefer a good decision today over a perfect one next week.

At Lucis, AI isn't just our product, it's our engine. 100% of our teams are equipped with the best AI agents. You have carte blanche to explore and automate everything that can be, so you can focus exclusively on high-value work.

## About Lucis

## Company Overview
- **One-liner**: Lucis is building Europe’s first AI-driven preventive health platform that combines blood testing with personalised action plans to help people add more healthy years to their lives.
- **Entity Type**: Private (YC-backed, Series A)
- **Headquarters**: Paris, France
- **Founded**: 2025
- **Founders**: Baptiste Debever and Max Berthelot

## Core Business
- **Primary industry**: Healthcare (Preventive health, longevity, healthtech)
- **Target customers**: B2C – health-conscious individuals in Europe who want to move from reactive to proactive healthcare
- **Mission or purpose statement**: “To make preventive health the default for every human in Europe” ([lucis.life/careers](https://www.lucis.life/careers))

## Products & Services
- **Lucis Platform**: An AI-powered preventive health service. Users book a blood draw at certified European labs (Eurofins network), analyse 60–110+ biomarkers, and receive a biological age, personalised scores (energy, inflammation, metabolism, hormones), and a medically reviewed action plan covering nutrition, sleep, supplements, exercise, and mental health. The platform connects to wearables (Withings, Garmin, Oura) for progress tracking and includes an AI chat (“AI doctor” agent). Available as two subscription plans:
  - **Discovery (490€/year)** – Two tests per year across 110+ biomarkers, 11 body systems, full dashboard & AI chat.
  - **Essential (190€/year)** – One annual test with 60 biomarkers, 5 body systems, and a personalised plan. ([lucis.life/press-kit](https://www.lucis.life/press-kit))

## Market Standing
- **Valuation/Market Cap**: Not publicly disclosed
- **Key Metric**: Total funding of $28.5M – $8.5M seed round and $20M Series A (as of June 2026) ([ycombinator.com](https://www.ycombinator.com/companies/lucis))
- **Notable Investors/Partners**: Y Combinator, General Catalyst, Kima Ventures, Motier Ventures, North South Ventures; plus angels including founders of Airbyte, Strapi, Sqreen, WePay, Plato, Veepee, and Zenly ([lucis.life/press-kit](https://www.lucis.life/press-kit))
- **Growth Signals**:
  - Serving 5,000+ paying members across France, Portugal, the UK, and Ireland ([ycombinator.com](https://www.ycombinator.com/companies/lucis))
  - Growing 10% week over week ([ycombinator.com](https://www.ycombinator.com/companies/lucis))
  - Doubled team size in the past year and on track to double again ([lucis.life/careers](https://www.lucis.life/careers))
  - Expanding lab partner network across Europe

## Competitive Advantages
- **AI-native architecture**: An AI “doctor” agent already shipping actionable protocols daily; entire company runs on AI agents for automation and efficiency ([lucis.life/careers](https://www.lucis.life/careers))
- **Comprehensive biomarker analysis**: 110+ biomarkers across 10+ body systems, unmatched breadth in the European consumer preventive health space
- **Full-stack integration**: Certified labs (Eurofins), wearable sync, AI interpretation, and clinical review – all in one platform
- **Data protection**: GDPR compliant and ISO 27001 certified, with strict data standards that build trust ([lucis.life/careers](https://www.lucis.life/careers))
- **Founder-market fit**: Founders combine repeat startup experience with deep domain knowledge in biomarker science and longevity

## Strategic Focus
- **Scale across Europe**: Currently live in France, UK, Ireland, Portugal; aggressively expanding to more markets
- **Product depth**: Enhancing the AI reasoning engine and adding more integrations with labs and wearables to improve the action plan quality
- **Building the “OS” for preventive health**: Shifting from one-time tests to continuous, longitudinal health tracking and automated interventions ([lucis.life/careers](https://www.lucis.life/careers))

## Why Work Here
- **AI-native culture**: Every team member gets unlimited tokens and complete autonomy to automate low-value tasks, freeing time for high-impact work ([lucis.life/careers](https://www.lucis.life/careers))
- **Ownership ethos**: “We hire adults and treat them like owners” – competitive salaries and meaningful equity; you share in the company’s success ([lucis.life/careers](https://www.lucis.life/careers))
- **Flexibility**: Generous, mandatory vacation; wellness stipend; comprehensive health insurance; full access to the Lucis platform (including advanced blood panels) for you and your family ([lucis.life/careers](https://www.lucis.life/careers))
- **Continuous learning**: Budget for books, courses, and conferences; access to experts and mentors from the investor network
- **Work model**: Primarily in-person at the Paris hub; relocation support available for the right candidates; occasional remote flexibility for the right fit ([lucis.life/careers](https://www.lucis.life/careers))
- **Team composition**: Repeat founders, engineers, health science experts – small, ambitious team (currently 17) that moves fast and ships daily ([ycombinator.com](https://www.ycombinator.com/companies/lucis))

## Sources
1. [lucis.life/careers](https://www.lucis.life/careers)
2. [ycombinator.com/companies/lucis/jobs](https://www.ycombinator.com/companies/lucis/jobs)
3. [lucis.life/en/careers](https://www.lucis.life/en/careers)
4. [ycombinator.com/companies/lucis](https://www.ycombinator.com/companies/lucis)
5. [lucis.life/press-kit](https://www.lucis.life/press-kit)

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