---
title: 'Principal Machine Learning Engineer - Applied AI & LLMs (x/f/m) at Doctolib'
canonical: 'https://feeny.ai/job/principal-machine-learning-engineer-applied-ai-llms-x-f-m-doctolib-paris-sspbm7f1y049'
type: 'job'
last_seen: '2026-09-08'
---

# Principal Machine Learning Engineer - Applied AI & LLMs (x/f/m) at Doctolib

- **Company:** Doctolib
- **Location:** Paris, France
- **Posted:** 2026-05-29
- **Last confirmed live:** 2026-09-08
- **Apply:** https://job-boards.greenhouse.io/doctolib/jobs/7749352003

## Job description

## What you’ll do

We are looking for a Principal Machine Learning Engineer to join the DS & AI organization at Doctolib. This is a transversal force multiplier role operating across all AI teams: Clinical, Productivity, Phone Assistant and ASR. Rather than working within a single feature team, you will own the cross-cutting technical challenges: defining how Doctolib's product and AI teams build agentic solutions, standardizing ML evaluation frameworks, and spreading strong engineering practices across the org. You will unblock teams, shape architecture decisions, and take on the deep technical work that requires senior ML judgment at scale, directly impacting the daily lives of 400,000 healthcare professionals and the health of 80 million patients. Building at Doctolib means delivering innovative products that measurably improve outcomes for care teams and patients alike.

Technical Strategy & Architecture

- Own cross-team ML architecture decisions, from model selection to production deployment patterns and strategic build vs. buy decisions
- Define and drive adoption of rigorous evaluation frameworks across all AI teams, setting the standard for how Doctolib measures model and agentic performance
- Establish shared production infrastructure patterns for AI: model and prompt versioning, guardrails, uncertainty quantification, cost optimization, and observability
- Lead the technical design of agentic solutions and define how product teams across Doctolib build on top of AI capabilities
- Elevate technical standards across the DS & AI org by influencing Staff and Senior ML Engineers through architecture reviews, technical guidance, and practice propagation
- Partner with Product, Legal, and Compliance teams to ensure safe rollout and meet EU regulatory expectations (GDPR, MDR, EU AI Act)

## Who you are

Before you read on, if you don't have the exact profile described below, but you feel this job description matches your skill set, we still encourage you to apply.

You'll be a great fit if:

- You have 10+ years in ML/AI with 3+ years at Staff+ or Principal level leading complex, multi-team technical initiatives
- You have deep expertise in at least two of: clinical NLP, LLM fine-tuning and evaluation, automatic speech recognition, RAG systems, or reinforcement learning
- You are expert in Python, PyTorch/Transformers for training, and vLLM for inference with a track record deploying ML systems in production (AWS/GCP)
- You have a PhD in Computer Science, AI, Statistics, or related field (or equivalent research experience)
- You have exceptional communication skills and are able to align diverse stakeholders and explain complex technical decisions

Now it would be fantastic if you have:

- Publications in top-tier ML/AI conferences (NeurIPS, ICLR, ACL) or medical informatics venues
- Experience with EU healthcare regulations (GDPR, MDR, AI Act)
- Prior work with clinical data or healthcare applications

Life at Doctolib Tech

- Our solutions are built on a single fully cloud-native platform supporting web and mobile interfaces across multiple languages and healthcare specialties.
- Our stack includes Rails, TypeScript, Java, Python, Kotlin, Swift, and React Native.
- We leverage AI ethically to empower patients and professionals. Discover our AI vision [here](https://careers.doctolib.com/ai-careers/).

Want to learn more about our tech culture and environment? Visit the [Doctolib Tech site](https://careers.doctolib.com/tech-doctolib/).

## What we offer

- Free comprehensive health insurance for you and your children
- 25 days of paid vacation per year, plus up to 14 days of RTT
- Free mental health and coaching services through our partner Moka.care
- Work from abroad for up to 10 days per year thanks to our flexibility days policy
- Lunch vouchers with Swile card (€8.50 value, €4.50 covered by Doctolib)
- Work Council subsidy for sports club memberships or creative classes
- 50% reimbursement of your public transport subscription
- Parent Care Program: one additional month of leave on top of legal parental leave
- For caregivers and workers with disabilities: remote policy adaptation, extra medical leave, and psychological support
- Relocation support for international mobility
- Access to premium AI tools for development and dedicated training

The interview process

- HR Screen
- Hiring Manager Interview
- Technical Interview
- Technical Case Study
- Behavioral Interview
- At least one reference check

We want your experience to be clear, respectful, and transparent. Learn more on our [candidate experience page](https://careers.doctolib.com/tech-doctolib/getting-hired/).

Job details

- Permanent position
- Full-time
- Paris, France
- Hybrid work mode (up to 2 remote days per week)
- Start date: as soon as possible

We welcome everyone

At Doctolib, we believe in improving access to healthcare for everyone - regardless of where you come from or what you look like. We evaluate candidates based solely on qualifications and motivation, without any form of discrimination. We respect and celebrate diversity!

The more diverse ideas are heard, the more our product will truly improve healthcare for all. You are welcome to apply regardless of gender, religion, age, sexual orientation, ethnicity, disability, or place of origin.

To ensure equal opportunities, we invite you to exclude personal information (e.g., pictures, age) from your applications. If you have a disability, let us know if there's any way we can make the interview process smoother for you! Join us in building the healthcare we all dream of.

## Your data privacy

All information transmitted via this form is processed by Doctolib for application management. For more on how we process your data, click [here](https://doctolib.legal/B2C-Privacy-Policy-Career-FR). For inquiries or to exercise your rights, contact us at hr.dataprivacy(at)doctolib.com.

## About Doctolib

## Core Business
- **Primary industry**: Healthcare information technology (healthtech) / Software Development
- **Target customers**: B2B (healthcare professionals across 120+ specialties) and B2C (patients managing their health journey)
- **Mission or purpose statement**: “Build together the healthcare we all dream of” – making healthcare more human, sustainable, and accessible. The company is a certified B Corp and mission-driven.

## Products & Services
- **Appointment Booking** – 24/7 online scheduling, waitlist management, calendar optimization, reminders and delay notifications.
- **Practice Efficiency (Digital Secretariat)** – Tools for patient base management, task manager, openings/absences, recall campaigns, and analytics.
- **Clinical & Care Cooperation** – Electronic health records (EHR), document management, secure messaging, prescribing, billing engine, and AI assistants for documentation and decision support.
- **Health Companion (Patient App)** – A mobile app offering prevention campaigns, early detection programs, personalized guidance via an AI assistant, video consultations, and messaging with professionals.
- **AI Consultation Assistant** – Structured transcription of consultations; has supported 5 million consultations.
- **AI Phone Assistant** – Virtual assistant handling bookings and messages 24/7.
- **Financial Solutions** – Simplifies billing and insurance processes for healthcare professionals.
- **Platform & APIs** – Internal platform for modular development; data import/export, CRM integrations, and partner programs.

## Market Standing
- **Valuation/Market Cap**: Not disclosed (private company)
- **Key Metric**: Annual Revenue EUR 257.6M (latest available); Total Funding USD 816M across 10 rounds
- **Notable Investors/Partners**: General Atlantic (lead in Series E), Eurazeo (Series D lead), Accel (Series B lead), and others. Acquired Dott.it, Tanker, and Appocrate.
- **Growth Signals**: 
  - 90 million patients and 420,000 healthcare professionals use the platform.
  - 2,900+ employees (up from ~2,618 as per LinkedIn; monthly headcount growth +1.0%).
  - Operating in France, Germany, Italy, Netherlands, with presence in Switzerland and UK.
  - Tech team of 900+ experts; AI features deployed in production (e.g., AI Consultation Assistant used in 5M consultations).

## Competitive Advantages
- **Network effects**: Large, two-sided marketplace connecting millions of patients with hundreds of thousands of professionals across Europe.
- **Deep healthcare expertise**: Over a decade of experience, solutions adapted to 120+ specialties and local regulations.
- **AI-first innovation**: Proprietary datasets, research lab, and production AI assistants that improve clinical efficiency.
- **Trust and compliance**: Certified B Corp, ISO 27001, HDS (health data hosting) – high security and privacy standards.
- **Platform modularity**: Cloud-native, distributed architecture that allows rapid adaptation to new countries and specialties.

## Strategic Focus
- **AI integration**: Scaling AI Consultation Assistant, AI Phone Assistant, and AI-powered clinical decision support.
- **Preventive and continuous care**: Shifting from reactive treatment to proactive health management via the Health Companion app.
- **Geographic expansion**: Deepening presence in existing European markets and entering new regions.
- **Platform modularization**: Building reusable components to accelerate product development and partner integrations.
- **Mission-driven growth**: Maintaining B Corp status while expanding revenue and impact.

## Why Work Here
- **Culture**: Mission-driven, B Corp certified, collaborative environment focused on social impact. Employees report a strong sense of purpose.
- **Work policy**: Flexible – hybrid and office-based modes available. Option to work from EU countries and the UK for up to 10 days per year.
- **Benefits**:
  - Health insurance 100% paid for employee and children.
  - 25 paid vacation days + up to 14 RTT days annually.
  - Free mental health and coaching services (Moka.care).
  - On-site gym with group classes (Paris office).
  - One additional month of parental leave on top of legal leave (Parent Care Program).
  - Lunch vouchers (Swile card), sports/club subsidy.
  - Solidarity Days (2 days/year for health charities).
- **Engineering culture**: 900+ tech team, dedicated onboarding (Doctolib Academy), continuous training, access to best AI tools, and internal mobility opportunities.
- **Employer rating**: 3.6/5 on LinkedIn (923 reviews) – work-life balance 3.7, culture 3.7, compensation 3.3.

## Sources
1. [careers.doctolib.com](https://careers.doctolib.com/)
2. [careers.doctolib.com/tech-doctolib](https://careers.doctolib.com/tech-doctolib/)
3. [linkedin.com/company/doctolib](https://www.linkedin.com/company/doctolib)
4. [jobsbyculture.com/companies/doctolib](https://jobsbyculture.com/companies/doctolib)
5. [welcometothejungle.com/en/companies/doctolib](https://www.welcometothejungle.com/en/companies/doctolib)

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