---
title: 'Research Engineer, Sandboxes at Mistral'
canonical: 'https://feeny.ai/job/research-engineer-sandboxes-mistral-paris-46kamrmz23tw'
type: 'job'
last_seen: '2026-10-18'
---

# Research Engineer, Sandboxes at Mistral

- **Company:** [Mistral](https://feeny.ai/companies/mistral)
- **Location:** Paris, France
- **Employment:** full-time
- **Posted:** 2026-10-16
- **Last confirmed live:** 2026-10-18
- **Apply:** https://jobs.ashbyhq.com/mistral.ai/736b11b6-a4f3-4ea8-b126-4d8e14fc0220

## 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

As a Research Software Engineer on the Sandboxes team, you will design, build, and operate the platform that runs isolated environments for untrusted code at massive scale. Our work spans distributed systems, low-level virtualization, and product-minded platform design. Engineers on this team move between deep infrastructure work and understanding how researchers actually use the platform. This is a software engineering role, not an ML research role. You do not need prior ML experience; what matters is writing clean, reliable systems code that scales. You will join a small, senior team where the wrong hire is worse than no hire.

## What You Will Do

- Design, build, and operate the sandboxing platform that runs untrusted code at scale across multiple Kubernetes clusters, from our own bare metal data centers to hyperscalers.
- Develop the sandbox runtime leveraging Firecracker, enabling fast startup, snapshotting, and efficient scheduling without blocking expensive hardware.
- Obsess over performance and latency optimisation allowing us to reach millions of concurrent sandboxes.
- Write robust, well-tested systems code in Rust and Python; review code, CI/CD, and observability across the platform.
- Own cross-cluster networking, security boundaries, isolation guarantees and monitoring for suspicious activity.
- Collaborate with researchers and ML engineers who use sandboxes for synthetic data generation and RL training, turning their needs into platform features.

## What We're Looking For

- A strong background in software engineering and distributed systems, with experience building and operating large-scale infrastructure.
- Deep expertise in at least one of: Kubernetes and cluster operations, cross-cluster networking, observability, or low-level virtualization.
- Fluency in Python or Rust; comfortable writing systems code where performance and security matter.
- Strong software-design instincts: modular code, testing, CI/CD, observability, and a bias for reliability.
- A self-starter who learns fast. Core skills matter more than specific tools — we value meta-learning ability and motivation highly.
- Low-ego, collaborative, and comfortable with ambiguity in a small, high-ownership team.

Nice-to-haves

- Experience with Firecracker, microVMs, or similar virtualization technologies.
- Product-mindedness: understanding of how sandboxes are used for synthetic data generation or RL training.
- Experience with GPU clusters, CUDA, or ML workloads.
- Prior SRE or platform engineering experience at scale.
- Open-source contributions or widely used internal tools.

## 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

- [Research Engineer - Search and Services](https://feeny.ai/job/research-engineer-search-and-services-mistral-paris-ye59bh3td0ja) — Paris, France
- [Head of Solutions Operations](https://feeny.ai/job/head-of-solutions-operations-mistral-paris-xz8jz5pem2pq) — Paris, France
- [Research Engineer, Orchestral](https://feeny.ai/job/research-engineer-orchestral-mistral-paris-8s9hk6k9gn0a) — Paris, France
- [Account Executive, Enterprise - Montreal](https://feeny.ai/job/account-executive-enterprise-montreal-mistral-montreal-65qsjmnd6t8t) — Montréal, Canada
- [Account Executive, Enterprise - Toronto](https://feeny.ai/job/account-executive-enterprise-toronto-mistral-toronto-wczsyzg1aqy8) — Toronto, Canada
- [IP & Licensing - Intern](https://feeny.ai/job/ip-licensing-intern-mistral-paris-naz5cg7zq4fa) — Paris, France
- [Finance Data Annotation Quality Analyst](https://feeny.ai/job/finance-data-annotation-quality-analyst-mistral-paris-xxfhpz44fyww) — Paris, France
- [Internal Event Manager - Paris](https://feeny.ai/job/internal-event-manager-paris-mistral-paris-29j9wtm68ywx) — Paris, France
- [Research Engineer, GPU Performance](https://feeny.ai/job/research-engineer-gpu-performance-mistral-paris-z76kvvmxbtz8) — Paris, France
- [Workplace Operations Manager](https://feeny.ai/job/workplace-operations-manager-mistral-san-francisco-29z7psa3b9rr) — San Francisco, CA