Mistral

Applied Scientist (Internship) at Mistral (Paris, France)

Mistral· Paris, France·

Role details

Employment
Internship

Mistral at a glance

A French AI lab building open and frontier-grade large language models, with the full developer and enterprise stack around them.

Mistral is a French AI lab that builds open and frontier-grade large language models and sells the full stack around them: developer tooling, an agent studio, consumer and enterprise apps like Le Chat and Vibe, custom model training, and its own GPU compute. Its edge is deployment control, with open weights, EU hosting, and self-hosting for regulated and sovereign buyers.

$3B+ raised · latest: Series C · 1.7B euros · Sept 2025 · backed by ASML, Nvidia, Andreessen Horowitz, DST Global

Job description

About Mistral

Mistral provides full-stack AI solutions: from frontier models to developer tools, applications, and compute. We partner with enterprises tackling the hardest problems—across high-stakes industries like finance, manufacturing, defense, healthcare, and the public sector—co-creating customized AI systems that they can run on their terms. We are a dynamic, collaborative team passionate about AI and its potential to transform society. Our diverse workforce thrives in competitive environments and is committed to driving innovation. Our teams are distributed between Europe, North America, Asia and the Middle East. We are creative, low-ego and team-spirited.

The Role

Mistral AI is seeking Applied Scientist Interns and Research Engineer Interns to drive innovative research and collaborate with clients on complex research projects. You will develop SOTA models across different modalities such as text, image, and speech. By developing novel methods and research ideas you will apply these models across a diverse set of use cases and domains. Working cross-functionally with both external and internal science, engineering, and product teams you will deliver high-impact AI solutions that turn the needle.

What You Will Do

  • Run pre-training, post-training and deploy state of the art models on clusters with thousands of GPUs.
  • Generate and curate data for pre-training and post-training, working on evaluations and making sure the model's performance beats expectations.
  • Develop the necessary tools and frameworks to facilitate data generation, model training, evaluation and deployment.
  • Collaborate with cross-functional teams to tackle complex use cases using agents and retrieval pipelines.
  • Manage research projects and communications with client research teams.

What We're Looking For

  • Fluent in English with excellent communication skills — at ease explaining complex technical concepts to both technical and non-technical audiences.
  • Expert with PyTorch or JAX.
  • Not afraid of contributing to a big codebase; finds their way around independently with little guidance.
  • Writes clean, readable, high-performance, fault-tolerant Python code.
  • Doesn’t need roadmaps: moves independently and navigates uncertainty with confidence.
  • Low-ego, collaborative and eager to learn.
  • Track record of success through personal projects, professional projects or academia.

Nice to have

  • Pursuing a PhD / Master in a relevant field (Mathematics, Physics, Machine Learning) — exceptional candidates from other backgrounds welcome.
  • Preferred duration: at least 6 months. Priority to candidates about to finalise their studies.
  • Research experience in agents, multimodal models, world models, robotics, diffusion models, cybersecurity, 3D understanding/generation, or time-series analysis.
  • Contributions to a large open-source or industry codebase.
  • Publications in top academic journals or conferences.
  • Enjoys improving existing code: typing, tests, CI pipelines.

Location & work authorization: This internship is available only in France or the UK. Please apply only if you have the required work authorization to complete the internship in the relevant country for its full duration.

What We Offer

We offer a comprehensive benefits package designed to support your well-being, growth, and work-life balance. Benefits vary by country and may include healthcare coverage, parental leave, retirement plans, relocation support, wellness programs, meal and transportation allowances, and other location-specific perks. For the most up-to-date details on benefits available in your location, please refer to our Benefits page.

Privacy Policy Your privacy matters to us. You can learn more about how we handle your personal data in our Applicant Privacy Policy.

Why work at Mistral

  • Culture: Flat structure, high ownership, low ego, and a "builders, not order takers" mentality. The company values audacity, speed, rigor, and customer centricity.
  • Remote/Hybrid/Office: Based in Paris (15 rue des Halles); relocation support and visa sponsorship offered. Specific remote/hybrid policy not detailed, but global team suggests flexibility.
  • Notable perks and benefits (from careers page):
    • 20 weeks paid parental leave for all birthing parents.
    • 100% employer-sponsored medical, dental, and vision coverage for employees and dependents.
    • 6% 401k match (US) / 5% pension contribution (UK).
    • Childcare support (reserved daycare seats or financial assistance).
    • Meal allowances and transportation support.
    • Fitness and wellness subsidies.
    • Relocation and settling-in services.
    • Financial and career planning support.
  • Team composition: 900+ employees from 30+ nationalities; 50% female leaders.
  • Interview process: For science, product, and engineering roles: intro conversation → 2-5 technical exercises → 1-3 interviews (hiring manager + teammates) → values conversation → reference checks.

Application questions