---
title: 'Research Engineer - Cybersecurity (RL Environments) at Mistral'
canonical: 'https://feeny.ai/job/research-engineer-cybersecurity-rl-environments-mistral-paris-pk0ygtgxe7g4'
type: 'job'
last_seen: '2026-11-08'
---

# Research Engineer - Cybersecurity (RL Environments) at Mistral

- **Company:** [Mistral](https://feeny.ai/companies/mistral)
- **Location:** Paris, France
- **Employment:** full-time
- **Work type:** hybrid
- **Posted:** 2026-09-25
- **Last confirmed live:** 2026-11-08
- **Apply:** https://jobs.ashbyhq.com/mistral.ai/818ab64d-6d6d-4e3e-9f6c-cc50ffd3e76c

## 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

Cybersecurity is one of the areas where AI could do the most good — and one where the capability must be built with particular care. As a Research Engineer on this track, you'll push our models' capabilities in vulnerability discovery and remediation, security analysis, incident response, and across the offensive-to-defensive spectrum of cybersecurity, and it will be your job to develop that ability deliberately and safely. The work sits at the meeting point of research and engineering: you'll devise new approaches and be the one to implement them. Concretely, that means designing and building RL environments that reproduce realistic security scenarios, pipelines that generate synthetic training instances at scale, and experiments and evaluations that show what our models can actually do. Your results feed directly into the production training runs that shape our frontier models, in close collaboration with Mistral's researchers, engineers, and security specialists. Security specialists and ML engineers are both welcome here — what matters is that you can hold your own in both worlds, and are eager to go deeper on the one you know less.

## What You Will Do

- Design and implement RL environments simulating cybersecurity scenarios.
- Build the pipelines and infrastructure that generate synthetic cybersecurity training instances at scale — thousands of scenarios, not one hand-crafted exercise.
- Conduct experiments and evaluations of model capabilities on these environments, from quick prototypes to controlled benchmark runs.
- Own the infrastructure behind the environments: containers, sandboxes, VMs, cloud deployments, and orchestration (Kubernetes), all managed as code.
- Partner with researchers and security specialists across Mistral, distilling their domain expertise into reproducible environments and datasets.
- Write clear, efficient code in Python and enforce strong software-design practices: testing, code review, CI/CD.

## What We're Looking For

- Hands-on expertise in offensive and/or defensive cybersecurity: vulnerability analysis, web/network/cloud security, secure coding practices, and SOC.
- Strong software engineering skills: clean, reliable, well-tested code — not just exploit scripts.
- Fluency in Python plus comfort reading lower-level languages (C/C++) for vulnerability analysis.
- DevOps experience: Docker, Kubernetes, cloud deployments, sandboxed or simulated environments.
- A pragmatic research-to-engineering mindset: ship a working first version, then refine and scale it.
- Working knowledge of RL techniques and LLM training methodologies, or strong motivation to develop it.
- Self-starter, low-ego, collaborative — comfortable working across research and engineering.

Nice-to-haves

- CTF, cyber-range, or bug-bounty experience — as a player, challenge author, or platform builder.
- A research background in cybersecurity, academic or industrial, or in another experimental discipline.
- Prior experience building RL environments or large-scale ML training infrastructure.
- Relevant open-source contributions and projects.

## 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](https://app.notion.com/p/mistralai/Benefits-at-Mistral-36e6ba59a7fe836b93dd01737fcc27ef?source=copy_link).

Privacy Policy Your privacy matters to us. You can learn more about how we handle your personal data in our [Applicant Privacy Policy](https://legal.mistral.ai/terms/applicant-privacy-policy).

## About Mistral

## Company Overview
- **One-liner**: Mistral is a French AI company building open, frontier-grade large language models, developer platforms, and applied AI solutions for enterprises and governments.
- **Entity Type**: Private (Series C)
- **Headquarters**: Paris, France (15 rue des Halles)
- **Founded**: April 2023
- **Founders**: Arthur Mensch (CEO), Guillaume Lample (Chief Science Officer), Timothée Lacroix (CTO)

## Core Business
- **Primary industry/industries**: Artificial Intelligence, Large Language Models, Enterprise AI Software
- **Target customers**: B2B, Enterprise, Government, and Developers (B2D)
- **Mission or purpose statement**: "To make frontier AI open to all, and together solve the world's hardest problems."

## Products & Services
- **Mistral Large**: Frontier-grade large language model for complex reasoning and enterprise tasks.
- **Mistral Small 3**: Efficient, lightweight model for cost-sensitive deployments.
- **Mistral Code / Vibe**: AI agent for long-horizon, autonomous software development and task completion.
- **Le Chat**: Consumer-facing AI assistant and chatbot.
- **Mistral OCR 4**: State-of-the-art document intelligence model for extracting and understanding text from images and PDFs.
- **Mistral Forge**: Custom model development service for training, aligning, and evaluating proprietary AI models on private data.
- **Mistral Studio**: Platform for building, testing, and running AI agents and applications with full control.
- **Mistral Compute**: Infrastructure and orchestration platform for frontier-scale training and inference (edge to cloud).
- **Mistral Search Toolkit**: Tools for integrating search and retrieval into AI applications.
- **Voxtral**: Voice AI model for speech-based interactions.

## Market Standing
- **Valuation/Market Cap**: $4.016 billion (latest reported valuation, per CB Insights; date not specified but likely post-Series C)
- **Key Metric**: Total funding raised across Seed, Series A, Series B, and Series C rounds (specific amounts not disclosed in search results).
- **Notable Investors/Partners**: Not explicitly named in search results, but the company partners with organizations in finance, manufacturing, defense, energy, and the public sector.
- **Growth Signals**: 
  - Rapid scaling: 900+ employees across 30+ nationalities as of mid-2026.
  - 50% of leadership roles held by women.
  - Key product launches on a near-monthly cadence (e.g., Mistral OCR, Forge, Vibe, Compute, Search Toolkit, Voxtral).
  - Strong presence in high-stakes, regulated industries (defense, energy, public sector).

## Competitive Advantages
- **Open-source DNA**: Commitment to openness, transparency, and cost efficiency differentiates Mistral from closed, Big Tech AI labs.
- **Full-stack ownership**: Controls the entire stack from frontier models to developer tools, applications, and compute infrastructure, enabling deep customization and reliability.
- **European leadership**: Positioned as a sovereign, European AI champion, appealing to governments and enterprises seeking data control and regulatory compliance.
- **Speed and rigor**: Culture of rapid experimentation, iteration, and data-driven decision-making.

## Strategic Focus
- **Enterprise and government partnerships**: Co-creating tailored AI systems for mission-critical use cases in finance, manufacturing, defense, energy, and public sector.
- **Open platform ecosystem**: Expanding Mistral Studio and Forge to enable customers to build custom models and agents on their own data.
- **Infrastructure as a product**: Commercializing Mistral Compute to become a platform for others to train and run AI workloads.
- **Continuous model innovation**: Releasing new frontier models and capabilities (OCR, voice, code agents) at a rapid pace.

## Why Work Here
- **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.

## Sources
1. [Mistral AI - About Page](https://mistral.ai/about/)
2. [Mistral AI - Careers Page](https://mistral.ai/careers/)
3. [Mistral AI - Homepage](https://mistral.ai/)
4. [CB Insights - Mistral AI Company Profile](https://www.cbinsights.com/company/mistral-ai)
5. [Mistral AI - LinkedIn](https://www.linkedin.com/company/mistralai)

## Other roles at Mistral

- [AI Scientist Intern - (Internship, Masters or Phd)](https://feeny.ai/job/ai-scientist-intern-internship-masters-or-phd-mistral-paris-43jzbe0kx4mv) — Paris, France
- [Engineering Manager, Serverless Containers](https://feeny.ai/job/engineering-manager-serverless-containers-mistral-paris-m06we4kkhq7s) — Paris, France
- [Engineering Manager, Fleet Delivery](https://feeny.ai/job/engineering-manager-fleet-delivery-mistral-paris-zsspnkk7y0k5) — Paris, France
- [Engineering Manager, Storage](https://feeny.ai/job/engineering-manager-storage-mistral-paris-ekf23bqg33ar) — Paris, France
- [Engineering Manager, Sandbox](https://feeny.ai/job/engineering-manager-sandbox-mistral-paris-5wx65405emb2) — Paris, France
- [Senior Engineering Manager, IaaS](https://feeny.ai/job/senior-engineering-manager-iaas-mistral-paris-n545rbk6r28j) — Paris, France
- [Forward Software Engineer](https://feeny.ai/job/forward-software-engineer-mistral-paris-gp4fe2vxk8pe) — Paris, France
- [Forward Software Engineer, Data](https://feeny.ai/job/forward-software-engineer-data-mistral-paris-5j7fnp825t2q) — Paris, France
- [Network Development Engineer, WAN & Edge](https://feeny.ai/job/network-development-engineer-wan-edge-mistral-paris-bb54t43jf8db) — Paris, France
- [Network Development Engineer, Data Center Fabrics](https://feeny.ai/job/network-development-engineer-data-center-fabrics-mistral-paris-3sgd968rfyhv) — Paris, France