We are an employee-centric company that truly appreciates our team members and their value to our customers and the missions they support. We pride ourselves on being forward-leaning thinkers and fostering teams that are and continue to be technically proficient and technically capable across a comprehensive range of cyber mission areas. OneZero full-time employees receive an extremely competitive benefits package that includes health/dental/vision/life insurance plans, 401K with company matching, PTO & paid holidays, employee referral program, and educational assistance. Additional details can be found on our website at:

Position Title: Information Systems Security Engineer (ISSE) Senior

Location: Alexandria VA

Clearance: Secret

Join OneZero's dynamic team as we seek driven Information Systems Security Engineers (ISSE) to bolster cybersecurity efforts for our valued US Coast Guard (USCG) customers. In this role, you'll play a pivotal part in refining and fortifying enterprise Endpoint Detection and Response as well as Security Information and Event Management (SIEM) solutions and services. Your mission? Ensuring that our technologies adhere rigorously to DoD cybersecurity engineering standards and policies, both in their development and ongoing maintenance. You'll serve as a key conduit between the CG C5ISC engineering and Information Systems Security teams, facilitating seamless collaboration to achieve system Authorization to Operate (ATO) milestones and to sustain security throughout the Risk Management Framework's Continuous Monitoring phase. Step into a role where your expertise shapes the security landscape for a critical maritime institution.

Job Summary

• Participate in the design and validation of security controls and hardening requirements within USCG EDR and SIEM capabilities.
• Conduct comprehensive security assessments identifying vulnerabilities and the remediation efforts of those findings.
• Serve as the engineering team's primary engagement point for the ISSO team in support of RMF Security Assessment and Authorization (SA&A) and Continuous Monitoring tasks
• Support the system ATO effort by identifying, collecting, and creating required SA&A artifacts such as system Visio drawings, local policies and plans, screenshots and extracts, STIG Checklists, and others as requested by the ISSO team.
• Assist in the configuration and management of EDR, SIEM, and supporting infrastructures
• Develop and maintain secure network architectures and system configurations.
• Work with system owners and developers to integrate security controls into system development and implementation processes.
• Stay current with evolving security threats, vulnerabilities, and industry best practices.
• Collaborate with ISSO and other DHS teams on incident response and remediation efforts.
• Mentor and guide junior ISSO staff, fostering professional development.

• 7+ years of direct experience serving as an Information Systems Security Engineer (ISSE) within the DoD/Federal Government. USCG experience is a plus.
• Proven track record of success in designing, implementing, and maintaining secure IT systems, demonstrating innovation, initiative, and problem-solving skills.
• In-depth understanding of information security principles and best practices, including network security, cybersecurity engineering, cryptography, system security, vulnerability management, and incident response.
• Working knowledge of the DoD RMF Security Assessment methodology and tools such as eMASS and ACAS.
• Familiarity with cybersecurity EDR and SIEM technologies such as Trellix, Microsoft Sentinel and Defender, Tanium, Elastic, etc.
• Familiarity with common IT infrastructure types, including physical and virtualized servers (Microsoft, Linux).
• Familiarity with cloud hosting environments and service types (Azure, AWS, SaaS, PaaS, IaaS), the DoD Cloud SRG.
• Experience with relevant security frameworks and standards, such as the NIST Cybersecurity Framework, FISMA, RMF, FedRAMP, and the DoD Cloud Services Approval Process.
• Demonstrated experience in creating system drawings in Microsoft Visio and usage of other Microsoft Office productivity applications.
• Excellent analytical and problem-solving skills.
• Strong written and verbal communication skills.
• Ability to work independently and as part of a team in a fast-paced environment.