Senior Linux Infrastructure Engineer

We are seeking an experienced Senior Linux Infrastructure Engineer to maintain, secure, troubleshoot, and improve enterprise Linux infrastructure in a high-availability financial technology environment.

This hands-on position supports Linux servers, Kubernetes-based applications, identity and access management, patching, automation, and software development teams. The engineer will also provide secondary support for AWS, certificate management, and related infrastructure services.

The ideal candidate is a self-starter who takes ownership of their systems and projects, works effectively independently or collaboratively, and approaches troubleshooting with an understanding of the entire technology environment. This position is essential to strengthening operational coverage, reducing single-person dependencies, and supporting expanding trading operations.

What you'll do

• Administer, maintain, secure, and troubleshoot enterprise Linux environments, primarily RHEL and Ubuntu.
• Support physical servers, virtual machines, storage, networking, and Linux-based applications.
• Manage operating system patching, upgrades, performance, capacity, and lifecycle management.
• Administer Linux virtualization technologies, including KVM.
• Maintain reliable, documented, and recoverable production infrastructure.
• Develop standardized configurations, operational procedures, and automation.

• Integrate Linux authentication and authorization with Microsoft Active Directory using SSSD, realmd, Kerberos, LDAP/LDAPS, or equivalent technologies.
• Implement centralized, group-based access management and least-privilege permissions.
• Manage sudo policies, SSH access, service accounts, administrative privileges, and Linux RBAC-equivalent controls.
• Support account provisioning, deprovisioning, periodic access reviews, and access auditing.
• Collaborate with Windows and identity engineering teams to maintain consistent access controls across platforms.

• Manage Linux patching using enterprise patch-management or configuration-management platforms.
• Maintain package repositories, patch schedules, compliance reporting, and remediation tracking.
• Evaluate security updates, test changes, coordinate production patching, and verify results.
• Automate patch deployments and validation where appropriate.
• Maintain approved security baselines and consistent system configurations.

• Support and troubleshoot production Kubernetes clusters and containerized applications.
• Diagnose issues involving nodes, pods, deployments, networking, storage, ingress, resource utilization, and cluster services.
• Distinguish platform and infrastructure problems from application-level failures.
• Administer Kubernetes RBAC, name spaces, service accounts, and access permissions.
• Support cluster monitoring, upgrades, backup, and recovery.
• Collaborate with development teams on deployment issues and incident resolution.

• Provide Linux, container, and infrastructure support to software development teams.
• Assist with application deployment, troubleshooting, and performance optimization.
• Support Git Lab, CI/CD pipelines, container registries, and development tooling.
• Help maintain consistent development, testing, and production environments.
• Support Infrastructure as Code and deployment automation initiatives.

• Provide operational support for AWS infrastructure, including EC2, IAM, VPC networking, and related services.
• Assist with certificate issuance, renewal, troubleshooting, and lifecycle management.
• Support PKI, TLS configurations, and secrets-management platforms such as Hashi Corp Vault.
• Develop sufficient cross-training and documentation to provide independent coverage for critical services.

• Independently investigate and resolve production issues across applications, operating systems, virtualization, networking, and storage.
• Take ownership of assigned incidents and projects through resolution and verification.
• Perform root-cause analysis, participate in post-incident reviews, and implement corrective improvements.
• Identify infrastructure risks and proactively recommend improvements.
• Improve monitoring, documentation, automation, and operational procedures.
• Participate in change management, disaster recovery testing, and business continuity planning.
• Support…