Senior Linux Infrastructure Engineer

About the role

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

Linux infrastructure and systems administration

•       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.

Identity, access management, and RBAC

•       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.

Patching and configuration management

•       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.

Kubernetes and container support

•       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, namespaces, service accounts, and access permissions.

•       Support cluster monitoring, upgrades, backup, and recovery.

•       Collaborate with development teams on deployment issues and incident resolution.

Software development and DevOps support

•       Provide Linux, container, and infrastructure support to software development teams.

•       Assist with application deployment, troubleshooting, and performance optimization.

•       Support GitLab, CI/CD pipelines, container registries, and development tooling.

•       Help maintain consistent development, testing, and production environments.

•       Support Infrastructure as Code and deployment automation initiatives.

Cloud, certificates, and supporting services

•       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 HashiCorp Vault.

•       Develop sufficient cross-training and documentation to provide independent coverage for critical services.

Operational reliability and continuous improvement

•       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 production infrastructure during assigned trading hours and scheduled on-call coverage.

Compliance and security

•       Support infrastructure controls aligned with SOC 2 Trust Services Criteria and organizational security policies.

•       Maintain audit evidence supporting access management, patching, change control, logging, and operational procedures.

•       Participate in SOC 2 readiness assessments, audits, remediation, and control improvements.

•       Apply approved security configurations and vulnerability remediation procedures.

•       Collaborate with cybersecurity leadership on infrastructure risks and improvements.

Collaboration, documentation, and mentorship

•       Work independently and collaboratively across infrastructure, networking, cybersecurity, and software development teams.

•       Maintain clear documentation, runbooks, and system configuration records.

•       Share knowledge and participate in cross-training to reduce single-person dependencies.

•       Willingly mentor colleagues, provide technical guidance, and contribute to team development.

•       Communicate progress, risks, technical findings, and recommended improvements.

Qualifications

Required

•       5+ years of professional Linux systems engineering or administration experience, or equivalent demonstrated expertise.

•       Strong RHEL administration and troubleshooting experience; familiarity with Ubuntu or comparable Linux distributions.

•       Experience integrating Linux authentication and access management with Microsoft Active Directory.

•       Strong understanding of Linux permissions, sudo, SSH, PAM, Kerberos, and group-based access management.

•       Experience using an enterprise Linux patch-management or configuration-management platform, including patch deployment, compliance reporting, and remediation.

•       Hands-on experience supporting and troubleshooting Kubernetes clusters and containerized applications.

•       Ability to distinguish application problems from operating system, Kubernetes, networking, storage, and other infrastructure issues.

•       Experience supporting software development teams and application deployment environments.

•       Experience with Bash, Python, Ansible, or comparable scripting and automation technologies.

•       Working knowledge of AWS infrastructure and cloud operations.

•       Experience working in, supporting, or preparing an organization for a SOC 2 audit or comparable controls-based compliance program.

•       Experience with production change management, incident response, and operational documentation.

•       Strong analytical, communication, collaboration, and independent problem-solving skills.

•       Willingness to mentor colleagues and share technical knowledge.

Preferred

•       Hands-on experience with Red Hat Satellite for Linux lifecycle and patch management.

•       Experience with Tanium for endpoint management, patching, inventory, or compliance.

•       Advanced Kubernetes administration, security, RBAC, and cluster troubleshooting.

•       Experience with GitLab CI/CD, Docker, Helm, Terraform, OpenTofu, or GitOps.

•       Experience with enterprise PKI, certificate automation, and HashiCorp Vault.

•       Experience with KVM virtualization and multi-datacenter infrastructure.

•       Familiarity with Prometheus, Grafana, centralized logging, and SIEM integration.

•       Background in cybersecurity best practices, Linux hardening, vulnerability management, and secure infrastructure design.

•       Experience with CIS benchmarks, SELinux, auditd, and privileged access management.

•       Experience supporting highly available financial technology or trading infrastructure.

•       Relevant certifications such as RHCE, CKA, or AWS certifications.