Senior Linux Systems Engineer - Hybrid

Project overview

About the mission

Lenstra was founded by passionate IT engineers with a track record of delivering high-quality solutions. We operate at the intersection of Cloud Computing, DevOps, Data Platforms, and IT Security, supporting leading clients in Banking, Insurance, Luxury, and Tech on their most demanding technical challenges. For this mission, we are recruiting a Senior Linux Systems Engineer directly at a major financial player based in Paris, whose name remains confidential at the client's request.

You will join a high-performance infrastructure team serving the research, trading, and enterprise teams, in an environment where availability and precision are non-negotiable.

The position

What we're looking for

Demanding about precision. When research and trading depend on your infra, "almost" is not enough.

Autonomous by nature. You will be trusted with the how, not just the what.

Rigorous with documentation. If it's not documented and reproducible, it's not finished.

Comfortable under pressure. Supplier exchanges and cross-functional coordination are part of the job, not the exception.

Technical skills

Essential:

In-depth expertise in GNU/Linux systems: administration, performance tuning, advanced troubleshooting.

Solid scripting skills in Bash and Python, to build open-source packages and automate recurring tasks.

Good command of physical servers: firmware, hardware monitoring, test scripts, automation of provisioning and lifecycle.

In-depth knowledge of core infrastructure services: DNS, DHCP, TFTP, PXE, LDAP.

Concrete experience with infrastructure as code and automation (Puppet, Ansible), with the ability to model infrastructure in code, industrialize it, and document it correctly.

• Evolve and migrate core infrastructure services (DNS, DHCP, LDAP, etc.) without disrupting a production trading environment.
• Design and specify the next generation of server platforms, from scratch.
• Develop and scale storage services to keep up with growing performance and capacity needs.
• Extend and modernize an internal HPC infrastructure that must continue to handle the load.
• Exchange directly with external suppliers on technical infrastructure topics — you will manage these relationships, not just relay messages.
• Coordinate with internal teams to bring projects, improvements, and deployments to fruition smoothly.
• Build and maintain the infrastructure on which the research, trading, and enterprise teams depend daily.

Nice to have

Experience with HPC environments, particularly Slurm.

Exposure to enterprise storage: EMC/Dell PowerMax, PowerStore, PureStorage FlashBlade/FlashArray, VAST — as well as iSCSI, Fibre Channel, NFS, SMB.

Enterprise virtualization, especially VMware vSphere Enterprise.

True understanding of containerization beyond basic Docker usage: Linux namespaces, cgroups, user namespaces, and subordinate UIDs/GIDs (subuid/subgid) for isolation and security.

What we offer

Daily rate from €700 to €750 — depending on seniority and interview performance, with no surprises.

12-month mission, renewable.

Start date: ASAP.

Hybrid, 3 days on-site.

Project details

• Start: ASAP
• Duration: 12 mois (renouvelables)
• Location: 75007 PARIS, FR
• Languages: French