Information Systems Security Engineer (ISSE), Level II at RSSi / OneZero Solutions in Baltimore, MD, USA
- Company: RSSi / OneZero Solutions
- Location: Baltimore, MD, USA
- Posted: Sep 19, 2026
- Type: Full-time
- Experience: 5+ years
Overview
The Information Systems Security Engineer serves as the OT Security Engineer for assigned USCG SFLC Operational Technology and provides the engineering half of the cybersecurity mission on this task order. Where the ISSOs own authorization and compliance, this role owns design: security requirements…
Job description
- The Information Systems Security Engineer serves as the OT Security Engineer for assigned USCG SFLC Operational Technology and provides the engineering half of the cybersecurity mission on this task order. Where the ISSOs own authorization and compliance, this role owns design: security requirements, defense-in-depth architecture, segmentation and boundary protection, and technical mitigation strategies that reduce risk without breaking operational capability.
- The position works across acquisition, engineering, and sustainment activities, from design reviews and change control boards through DevSecOps pipeline support, and provides independent cybersecurity engineering assessments of USCG C5ISR acquisition program deliverables.
Responsibilities
- Serve as the OT Security Engineer (ISSE) for assigned SFLC Operational Technology, providing cybersecurity engineering input, recommendations, and implementation assistance.
- Design and develop security requirements and defense-in-depth solutions that reduce cybersecurity risk while maintaining operational capability and compliance with DHS, USCG, and DoD policy.
- Support architecture-level and implementation-level engineering activities, maintaining a system-wide view of cybersecurity functions and requirements, and recommend risk mitigation at the architecture, design, and implementation levels.
- Evaluate newly identified threats and vulnerabilities affecting assigned OT, determine the need for additional safeguards, and recommend technical mitigation and implementation strategies.
- Assess proposed changes to assigned OT, operating environments, and mission requirements for impacts to cybersecurity architecture, security requirements, and continued compliance; recommend technical mitigations.
- Participate in acquisition, engineering, and system development activities including program and design reviews, Concept of Operations (CONOP) working groups, change control boards, technical exchange meetings, technical discussions, and trade studies.
- Identify cybersecurity integration issues arising from new or modified systems within existing SFLC infrastructure and recommend mitigation or resolution options that preserve security, interoperability, and operational capability.
- Apply cybersecurity and systems engineering principles and industry best practice to the design, development, integration, and implementation of security requirements, including secure architecture, secure design, software engineering methodologies, defense-in-depth, and secure coding techniques.
- Provide cybersecurity engineering input to development and engineering teams responsible for design, development, integration, modernization, and upgrade of assigned OT, including legacy OT.
- Interface with Government stakeholders to communicate cybersecurity requirements, technical risks, and mitigation options, and explain their impacts on system performance, operational capability, cost, and schedule in support of Government risk-management decisions.
- Design and evaluate cybersecurity requirements for trusted relationships and interconnections between assigned OT and external systems or architectures; recommend safeguards to protect information exchanges.
- Provide engineering support for the design of systems and networks spanning multiple enclaves or differing information protection requirements, and recommend security architecture, segmentation, boundary protection, and information-flow controls.
- Evaluate current and emerging cybersecurity technologies, threats, vulnerabilities, and best practices applicable to assigned OT and provide technical recommendations to improve resilience.
- Provide cybersecurity engineering assessments of USCG Command, Control, Communications, Computers, Cyber, Intelligence, Surveillance, and Reconnaissance (C5ISR) acquisition program deliverables in support of Independent Verification and Validation (IV&V), assessing requirements, architectures, standards, technical feasibility, and engineering content, and reporting findings and recommendations to the Government.
- Support DevSecOps activities for assigned OT, including cybersecurity engineering support for security dashboards and development of technical recommendations for vulnerability guardrails and thresholds for software and applications.
- Provide status reporting to the Program Manager and ISSM as required. [NOTE: unlike the four other labor CLINs, the SOW does not specify bi-weekly reporting or a monthly briefing for this position. Confirm the Government's expectation.]
Requirements
- No security clearance required. This position does not involve access to classified information or classified IT systems.
- S. citizenship is required in accordance with HSAR 3052.204-71 Alternate I.
- Five (5) or more years of cybersecurity engineering experience, including at least three (3) years in a security architecture or security engineering role supporting federal systems.
- Demonstrated experience translating security requirements into implementable technical designs and defense-in-depth architectures.
- Experience participating in formal engineering governance: design reviews, change control boards, technical exchange meetings, or trade studies.
- Experience designing or evaluating network segmentation, boundary protection, and information-flow controls across enclaves or differing protection levels.
- Experience assessing technical documentation and deliverables and producing written findings and recommendations for a Government customer.
- Must hold and maintain at least one active certification approved for Information Assurance System Architect and Engineer (IASAE) Level I or Level II. Any one of the following satisfies the requirement:
- CISSP - Certified Information Systems Security Professional (or CISSP Associate)
- CSSLP - Certified Secure Software Lifecycle Professional
- CASP+ - CompTIA Advanced Security Practitioner
- Certification requirements are subject to confirmation against COMDTINST M2620.2 (series) Appendix D, the controlling USCG certification matrix. Verify the accepted certification list with the Program Manager before extending an offer.
- Evidence of active certification in good standing is required prior to onboarding. Waivers and exceptions to certification requirements will not be granted.
- Certifications must remain current, active, and in good standing throughout performance. Loss, lapse, or revocation of a required certification is grounds for removal from the contract. Continuing education required to maintain certification is at the employee's and company's expense.
- Ability to explain technical risk and mitigation trade-offs to non-engineering Government stakeholders in terms of performance, capability, cost, and schedule.
- Ability to read, write, speak, and understand English fluently.
- Security architecture and defense-in-depth design for OT, Platform IT, and legacy environments
- Network segmentation, boundary protection, enclave design, and information-flow control
- NIST SP 800-160 Vol 1, NIST SP 800-53 / 53B control selection and tailoring, NIST SP 800-37 RMF
- Interconnection and trusted-relationship design; ISA/MOU technical content
- DISA STIGs and Security Requirements Guides applied at the design stage
- Secure coding practice and software engineering methodologies
- DevSecOps tooling, security dashboards, and vulnerability guardrail/threshold design
- Independent Verification and Validation of technical and architectural deliverables
- DHS Systems Engineering Life Cycle (SELC) and USCG acquisition governance (MSAM / NMAP)
- No security clearance required. This position does not involve access to classified information or classified IT systems.
- S. citizenship is required in accordance with HSAR 3052.204-71 Alternate I.
- A favorably adjudicated Tier 1 background investigation (or higher) is required. Candidates without an existing investigation on file must complete an Electronic Application (eApp) for investigation processing.
- Note to recruiting: per the task order, the position is not billable until the selected candidate is fully cleared, has a CAC in hand, and has reported to the work site. Fill timelines should assume 30–90 days for investigation and CAC issuance.
- Bachelor's degree in engineering, computer science, cybersecurity, information systems, or a related field.
- Prior USCG, DHS, or DoD security engineering experience on Surface Domain OT, Platform IT, or C5ISR programs.
- Experience engineering security for OT/ICS environments with legacy components and constrained patching windows.
- CSSLP, CASP+, or equivalent in addition to the required baseline certification.
- Experience supporting DevSecOps pipelines, security dashboards, and automated vulnerability gating.
- Familiarity with NIST SP 800-160 Volume 1 systems security engineering.
- Master's degree in engineering, cybersecurity, or a related field.
About RSSi / OneZero Solutions
We are an employee-centric company that truly values our team members and the contributions they make to our customers and the missions they support. We pride ourselves on being forward-leaning thinkers and on building teams that are, and continue to be, technically proficient across a broad range of cyber mission areas. OneZero full-time employees receive a highly competitive benefits package, including health, dental, vision, and life insurance, a 401(k) with company matching, paid time off and holidays, an employee referral program, and educational assistance. Additional details are available on our website: https://www.onezerollc.com/careers/