Engineering Team Lead, Sandbox

Mistral.ai; Paris; Sur place; EUR 120 000 - 180 000; Plein temps

Avantages offerts par ce poste

Healthcare

Parental leave

Retirement plans

Relocation support

Wellness programs

Meal allowances

Transportation allowances

Résumé du poste

Mistral is seeking a senior engineering leader to manage and coach a team building the isolation layer for AI agents at scale. You will split time between architecture decisions and team leadership, hiring, feedback, and career growth.

You will own the security boundary, scale to thousands of sandboxed environments, write Go, and partner with product teams to drive robust backend/infrastructure for frontier AI workloads.

Qualifications

• 2+ years of real people leadership.
• Shipped production systems in Go.
• Hands-on contribution matters, but focus is on the team you build.
• Deep Linux internals: namespaces, cgroups, seccomp, virtualization (Firecracker).
• 8+ years building backend or infrastructure systems.
• Experience partnering with product, design, and business teams.

Responsabilités

• Build the isolation layer using microVMs/containers, namespaces, cgroups, seccomp, snapshot and restore.
• Own the security boundary of the platform.
• Scale to fleets with low latency and high concurrency for thousands of environments.
• Write Go and own architecture decisions for core primitives.
• Grow engineers and set ownership standards; coach team beyond comfort zone.
• Own people management: hiring, performance, growth paths, feedback.
• Partner with Product Managers to translate frontier research into ship-ready primitives.

Connaissances

People leadership

Architecture leadership

Go

Backend/infrastructure

Cross-functional collaboration

Performance optimization

Low-ego, team-first mindset

Outils

Go

Linux internals

Networking

Description du poste

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 team Mistral is building a sovereign AI cloud for Europe. Our customers in finance, healthcare, and the public sector run frontier models on European-jurisdiction infrastructure, and the Cloud Platform team builds the systems that make that possible - compute orchestration, Kubernetes, bare metal, storage, networking, and the datacenter fleet that runs it all. We run it all on our own metal, our own network, our own datacenters - which means when something breaks, the fix is ours to write. European Compute Units let enterprises commit to multi-year capacity on that infrastructure, and we are scaling toward a gigawatt of compute across Europe by 2030. You will design and ship the layer every sovereign AI deployment depends on and shape the team building it.

The Role

This is a people-leadership role from day one. You will manage the team - hiring, coaching, performance, growth paths, honest feedback - while staying close to the code: roughly half your time in architecture decisions and the hardest technical problems the team faces, the other half leading your squad. If you are looking for a senior IC role, this is not it. AI agents don't run in browsers. They run in sandboxes - and you will lead the team building ours. We build secure, isolated, network-controlled environments with snapshotting primitives, designed for AI agents and reinforcement-learning workloads. An RL training run doesn't need one environment; it needs thousands, created and destroyed every second. An agent needs to be sandboxed from the world while still feeling fast enough to be useful. That tension - airtight isolation, at fleet scale, at low latency - is the product. Your customers are the people building the next generation of AI software on our infrastructure; the primitives you ship become the runtime their agents live in.

What You Will Do

• Build the isolation layer: microVMs or containers, namespaces, cgroups, seccomp, snapshot and restore.
• Own the security boundary.
• Scale to fleets: creation latency, density, and lifecycle management for thousands of concurrent environments.
• Write Go alongside your team and own the architecture and the hardest implementation decisions.
• Grow the engineers, not just the software - set the standard for ownership and coach people past their comfort zone.
• Own people management for the team: hiring, performance, growth paths, and honest feedback.
• Partner with Product Managers to turn frontier research needs into shippable primitives.

What We're Looking For

• 2+ years of real people leadership.
• You have managed engineers - hired, coached, given honest feedback, and grown them.
• Hands-on contribution matters here, but this role is judged on the team you build and lead, not just the code you write.
• Deep Linux internals: namespaces, cgroups, seccomp, virtualization - ideally microVMs of the Firecracker class.
• You have shipped production systems in Go.
• Not dabbled.
• Shipped.
• You understand network isolation at the packet level - not just firewall rules.
• Performance instincts: you know what a syscall costs, and you have the profiles to prove you've cared.
• 8+ years building backend or infrastructure systems.
• You have partnered with product, design, and business teams to ship software that reached real users.
• A low-ego, team-first mindset.
• We care less about your exact domain and more about whether you are the kind of technical force other engineers want to work alongside.

What We Offer

We offer a comprehensive benefits package designed to support your well-being, growth, and work-life balance.

• healthcare coverage
• parental leave
• retirement plans
• relocation support
• wellness programs
• meal and transportation allowances
• other location-specific perks

For the most up-to-date details on benefits available in your location, please refer to our Benefits page.

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