ManTech seeks a motivated, career and customer-oriented Senior Cyber Security Engineer to join our team in Herndon, VA.   Responsibilities include but are not limited to:Implement and maintain cybersecurity solutions across a classified environment.Perform risk assessments, vulnerability scans, and system hardening in compliance with NIST 800-53 and RMF.Support the preparation and submission of security documentation for Authority to Develop (ATD) and Authority to Operate (ATO) under IC guidelines.Collaborate with system owners, ISSOs, ISSEs, ISSMs, engineers, and auditors during security assessments and continuous monitoring.Monitor and respond to security incidents, performing root cause analysis and remediation.Integrate security controls into DevSec Ops pipelines and cloud architectures (AWS, Azure, GCP or Oracle).Support development and implementation of security policies, plans, and SOPs.Stay current on evolving federal cybersecurity directives, threats, and compliance requirementsMinimum Qualifications:Bachelor’s degree in Cybersecurity, Computer Science, Information Systems, or 4+ years of additional cyber experience in lieu of degree5+ years of experience in cybersecurity or related IT security roles.Experience with NIST Risk Management Framework (RMF), FedRAMP, or DoD Cybersecurity Maturity Model Certification (CMMC).Experience working in air-gapped cloud environments.Experience supporting the Intelligence Community.Knowledge of system/network security principles and incident response practices.Preferred Qualifications:DoD 8570.01-M IAT Level II or III certification (e.g., Security+, CISSP, CEH, CISM).Experience with security tools (e.g., ACAS, Splunk, Tenable, Palo Alto, CrowdStrike, or similar).Experience with Scripting or automation (Python, Bash, PowerShell) to support security operations.Knowledge of STIGs, SCAP tools, and secure system baselining.Clearance Requirements:Active TS/SCI. Physical Requirements:Must be able to remain in a stationary position 50% of the time.Needs to occasionally move about inside the office to access file cabinets, officemachinery, etc.Frequently communicates with co-workers, management, and customers, which mayinvolve delivering presentations. Must be able to exchange accurate information inthese situations.