Senior Principal Cybersecurity Engineer: Splunk & SIEM Lead

MANTECH; Chantilly (VA); On-site; USD 180,000 - 240,000; Full time

Job summary

MANTECH in Chantilly, VA seeks a Senior Principal Cyber Security Engineer to design, deploy, and maintain secure data collection and monitoring solutions that enable informed decision‑making across the enterprise, supporting mission critical cybersecurity operations and resilience.

You will troubleshoot data ingestion, deploy Splunk add‑ons, implement RBAC, and develop accreditation materials and security documentation in accordance with DoD policy, DoD 8570 requirements, and C&A processes, with

Qualifications

• Bachelor’s degree or 4+ years cyber experience in lieu of a degree.
• 10+ years of cybersecurity experience.
• Experience with SIEM platforms and Splunk.
• Knowledge of Linux systems administration, TCP/IP networking, and system security.
• Knowledge of Certification and Accreditation (C&A) processes.
• Knowledge of DoD policy and technical security guidance for information systems.
• DoD Directive 8570.1 IAT Level II or higher certification, or ability to obtain within six months.
• Splunk certification is required.

Responsibilities

• Troubleshoot new and existing data collection issues to ensure accurate ingestion of security-relevant data.
• Diagnose and resolve system issues that impact stability, performance, or usability.
• Deploy, manage, and maintain Splunk Add-ons required for specific data sources.
• Develop and maintain documentation, including BOE artifacts, engineering documentation, change records, system security plans, and accreditation materials.
• Deliver a comprehensive Splunk deployment document detailing specifications and architecture for production environments.
• Implement and maintain RBAC to ensure data access on a need‑to‑know basis.
• Design and deploy Splunk forwarders using Deployment Server for rapid deployments.

Skills

SIEM experience

Splunk

Linux administration

Networking basics

DoD policy knowledge

C&A processes

IAT Level II certification

Documentation

Security engineering

Clearance TS/SCI

Education

Bachelor’s degree or equivalent cyber experience

Tools

Splunk

Red Hat/CentOS

Job description

MANTECH in Chantilly, VA seeks a Senior Principal Cyber Security Engineer to design, deploy, and maintain secure data collection and monitoring solutions that enable informed decision‑making across the enterprise, supporting mission critical cybersecurity operations and resilience.

You will troubleshoot data ingestion, deploy Splunk add‑ons, implement RBAC, and develop accreditation materials and security documentation in accordance with DoD policy, DoD 8570 requirements, and C&A processes, with