Senior Linux Infrastructure Engineer

About the role

We are seeking a senior Linux Infrastructure Engineer to own and evolve the systems layer of our production environment in Chicago. The role blends deep operational expertise with the ability to build and automate infrastructure, ensuring reliability, performance, and scalability across our services.

Key responsibilities

• Own Linux performance tuning, including CPU scheduling, NUMA placement, memory, I/O, and network stack optimization.
• Lead incident response, formulate hypotheses, conduct targeted tests, write post‑mortems, and implement preventive measures.
• Develop and maintain configuration management code using Salt, Ansible, Chef, or Puppet, treating it with the same rigor as application code.
• Design, deploy, and operate containerized workloads on Kubernetes or Nomad, managing resource limits, health checks, and failure modes.
• Automate operational tasks with Bash and Python, replacing manual runbooks with reliable tooling.
• Manage core network services such as DNS, DHCP, and TCP/IP troubleshooting, and operate traffic routing with Nginx and HAProxy.
• Support data‑plane services including Redis and RabbitMQ, and maintain virtualization platforms (VMware, Xen, KVM).
• Handle secret management using Vault and maintain observability stacks (Elastic, Nagios, CheckMK, Icinga).

Required profile

• 5+ years of hands‑on experience managing Linux production systems at scale.
• Proven track record of incident leadership and root‑cause analysis.
• Strong understanding of networking fundamentals and virtualization technologies.
• Experience building infrastructure as code and operating container orchestration platforms.
• Passion for deep technical investigation and continuous improvement.

Required skills

• Linux system administration
• Salt, Ansible, Chef or Puppet
• Kubernetes or Nomad
• Bash and Python scripting
• TCP/IP, DNS, DHCP
• Nginx, HAProxy
• Redis, RabbitMQ
• VMware, Xen, KVM
• Vault for secret management
• Elastic Stack, Nagios, CheckMK, Icinga
• Git version control