Sr Cyber Security Engineer

Constellis•Virtual, VA

1d•Remote

About The Position

The Senior Cyber Security Engineer will bridge the gap between "Compliance" and "Engineering." You will not just audit the system, you will help build it securely and own the cybersecurity workstream end-to-end. This role is responsible for achieving Authority to Operate (ATO) under DoD Risk Management Framework (RMF) standards among other federal certifications while embedding security automation directly into our CI/CD pipelines, and reporting program status and risk directly to LEXSO leadership. You will work side-by-side with backend and frontend engineers to harden the microservices architecture against evolving threats, and you will independently identify security gaps, drive architectural design decisions and shepherd remediation to completion.

Requirements

8+ years of experience in Cyber Security Engineering or DevSecOps.
Proven track record of achieving ATO (Authority to Operate) for a software system in a DoD/Federal environment
Hands-on experience with RMF, NIST 800-53, and DISA STIGs
Proficiency in scripting languages (Python, Bash) for automation
Experience with vulnerability scanning tools (ACAS/Nessus, SonarQube, Burp Suite)
Strong knowledge of Linux Security (SELinux, iptables, hardening)
Experience with CI/CD tools (GitLab CI, Jenkins) and Container Security (Docker/K8s)
Demonstrated ability to work autonomously — identify security gaps, drive architectural design decisions, and track implementation through to completion
Experience communicating technical findings and program status to executive leadership; able to translate risk and remediation into terms leadership can act on
Track record of ownership over requirements definition and progress reporting for cybersecurity workstreams
CISSP, CASP+, or Security+ CE (Required)
Active Secret Security Clearance
Bachelor’s degree in Computer Science, Cyber Security, or related technical discipline.

Nice To Haves

Experience securing cloud environments (AWS GovCloud / Azure Government)
Experience with FedRAMP authorization processes
Familiarity with "Zero Trust" architecture principles
Previous experience as a Software Developer before moving into Security
Prior experience as a technical lead or senior individual contributor with direct exposure to stakeholders

Responsibilities

Own the LEXSO cybersecurity program end-to-end – from gap identification through architectural design to implementation tracking
Report cyber risk posture and remediation progress; translate technical findings into terms leadership can act on
Define and maintain the cybersecurity requirements backlog and progress-tracking cadence
Lead the technical execution of the RMF process to achieve and maintain Authority to Operate (ATO) for the LEXSO platform
Implement security controls in accordance with NIST SP 800-53 and DoD SRG/STIGs
Generate and maintain artifacts required for eMASS, including SSPs, POAMs, and SARs
Conduct self-assessments using ACAS (Nessus) and SCAP Compliance Checker (SCC) to identify vulnerabilities
Integrate automated security testing (SAST/DAST) tools (e.g., SonarQube, OWASP ZAP) into the GitLab/GitHub CI/CD pipeline
Develop scripts (Python, Bash, Ansible) to automate patching and configuration management for Linux (RHEL/Ubuntu) servers
Implement Container Security scanning for Docker/Kubernetes environments to detect vulnerabilities before deployment
Enforce "Security as Code" principles using Terraform or Helm charts
Analyze vulnerability scan results and write the code/scripts to remediate findings (e.g., fixing SSH configurations, patching libraries, hardening NGINX)
Harden APIs and microservices by implementing secure authentication (OAuth2/JWT/mTLS) and encryption standards (FIPS 140-2)
Respond to zero-day threats and CVEs by rapidly deploying hotfixes to the production environment
Conduct threat modeling sessions with the engineering team to identify attack vectors in the multi-sensor architecture
Design and implement secure logging and auditing pipelines (ELK Stack/Splunk) to meet audit requirements
Advise on the secure architecture for integrating third-party sensors (LiDAR, Radar) and IoT devices
Other duties as assigned