Founded in 1989 and headquartered in Reston, Virginia, SOSi is a private defense and government solutions business specializing in advanced technology systems and mission support. Its capabilities include data science, software development, network engineering, intelligence, surveillance, and reconnaissance (ISR), and logistics.
SOSI is seeking a Senior Cybersecurity Engineer to serve as a technical subject matter expert supporting an enterprise cyber defense program for a federal customer. This senior, highly visible role sits at the intersection of security engineering, architecture, and operations. It shapes how the customer evaluates, integrates, and matures its defensive capabilities. The ideal candidate combines hands-on engineering depth with the judgment to advise government stakeholders on emerging threats and technologies. This position is located in the Washington, DC metropolitan area and requires the ability to obtain a Secret clearance.
The Senior Cybersecurity Engineer serves as a trusted technical advisor across a broad defensive cybersecurity portfolio. In this role, you will assess the customer’s security architecture, identify gaps, and design practical solutions that strengthen detection, response, and protection across on-premises, cloud, and mobile environments. You will lead technical evaluations and proofs of concept for new security technologies and translate findings into clear recommendations for leadership.
You will work closely with security operations, engineering, and system owner teams. Together, you will turn operational needs into defined security requirements and controls, help integrate security into development and deployment pipelines. The role also supports the customer’s adoption of emerging technology areas, including AI-enabled capabilities and cryptographic modernization. Success in this position requires technical breadth, sound engineering judgment, and the ability to communicate complex security concepts to both technical and non-technical audiences.
Five (5) years security-related experience
All interested individuals will receive consideration and will not be discriminated against for any reason.

SOSi solves the challenges of the modern mission. A leader in delivering transformational and trusted technology and mission solutions, SOSi supports clients across the aerospace, defense, and government services industry.
Where others see the size of the challenge, we succeed at delivering solutions! #ChallengeAccepted
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