Information System Security Engineer; ISSE) Senior - Top Secret Clearance Required

About Agile Defense

At Agile Defense we know that action defines the outcome and new challenges require new solutions. That’s why we always look to the future and embrace change with an unmovable spirit and the courage to build for what comes next.

Our vision is to bring adaptive innovation to support our nation's most important missions through the seamless integration of advanced technologies, elite minds, and unparalleled agility—leveraging a foundation of speed, flexibility, and ingenuity to strengthen and protect our nation’s vital interests.

Requisition #: 1925

Job Title: Information System Security Engineer (ISSE) Senior

Location: Huntsville, AL

Clearance Level: TS with SCI eligibility required to start job

Required Certification(s): One of the following: CCISO, CISA, CISM, CISSO, CISSP, CISSP-ISSEP, CPTE, CySA+, FITSP-A, GCSA, GSLC, or GSNA

Agile Defense is seeking a skilled Information System Security Engineer (ISSE) to support the FBI under Objective 2: ISSO/ISSE Program Management. The ISSE will provide technical security engineering expertise to help develop, implement, and sustain a methodology for categorizing FBI IT systems based on architecture, complexity, hosting environment, security posture, and mission requirements.

This role supports the technical analysis needed to differentiate systems by risk, technology stack, overlays, and operational dependencies, and to ensure those categorizations effectively inform labor allocation, reporting, and cost recovery. The ISSE will work closely with ISSOs, system owners, architects, and program leadership to maintain a scalable and compliant categorization framework aligned with FBI and federal standards.

• Support design and maintenance of a methodology to categorize FBI IT systems based on:
  Architecture and technology stack
  Security classification level
  FIPS-199 impact level
  National Security System designation
  Hosting environment (on-premises, Azure, AWS)
  CNSS 1253 overlays
  Data sensitivity and data types
  Mission/business function
  System complexity and integration dependencies
• Assess system architecture, interfaces, hosting models, and security control implications to help determine appropriate ISSO/ISSE support levels.
• Analyze traditional, hybrid, and cloud-based systems to distinguish technical support requirements.
• Support accurate grouping of systems based on risk, operational impact, engineering effort, and compliance obligations.
• Translate technical system attributes into labor mapping recommendations aligned to ITSSS labor categories and seniority levels.
• Partner with ISSOs and program leadership to ensure categorization decisions are technically sound, repeatable, and well documented.
• Contribute to documentation supporting system assignments, engineering rationale, and support models.
• Support chargeback and cost recovery efforts by aligning technical support effort with system and division-level reporting.
• Assist with automated or semi-automated workflows used for categorization, reporting, and cost assignment.
• Support updates to reporting tools and technical logic when policy, technology, or organizational changes occur.
• Contribute to RMF and system security engineering activities, including:
  Security architecture reviews
  Control implementation analysis
  Inheritance considerations
  Boundary analysis
  System interconnection analysis
  Technical documentation support
• Review and apply NIST, CNSS, and FBI guidance to ensure methodology remains compliant and current.
  Support continuous improvement of the categorization framework as new technologies and requirements emerge.

• Bachelor's degree in Information Security, Engineering, or related field.
• 8+ years of experience, or equivalent relevant work…