Information Systems Security Engineer, TS​/SCI Counterintelligence Polygraph

Location:
Alexandria, VA

Accrete is an agentic managed services company: an AI workforce that does high-stakes, judgement-heavy work for government and enterprise clients — at the economics of software, not labor.

At the core is Accrete’s Knowledge Engine, a dynamic context graph that captures an organization’s tacit knowledge, resolves data across silos, and builds a living, auditable ground truth. Expert agents reason against that ground truth to act on complex, high-stakes decisions — not just answer questions about them.

From national security to commercial operations, Accrete delivers the work on one platform, with unlimited expert agents and expert judgement.

As an Information Systems Security Engineer (ISSE) Mid, you will work at the intersection of software engineering, cybersecurity, systems architecture, and government security requirements
. You will help ensure that Accrete's AI and data systems are designed, deployed, and operated securely in mission-critical environments.

You will work closely with software engineers, Dev Ops, security teams, data scientists, product teams, and government stakeholders to identify security requirements, assess technical risks, implement security controls, and support authorization and accreditation activities.

The ideal candidate is technically hands‑on, understands modern software and cloud environments, and can translate security requirements into practical engineering solutions.

• Apply security engineering principles throughout the system development lifecycle
• Define and document system security requirements and technical security controls
• Analyze system architectures and identify security risks, vulnerabilities, and potential attack vectors
• Develop Authority to Operate (ATO)-ready security architectures for AI, data, cloud, and enterprise systems
• Work with engineering teams to incorporate security controls into system designs and implementations
• Support security assessments, risk assessments, vulnerability remediation, and continuous monitoring
• Develop and maintain system security documentation, diagrams, control implementations, and technical artifacts
• Evaluate proposed system changes for security impact
• Support security reviews of new technologies, integrations, APIs, infrastructure, and software components
• Ensure systems are designed according to applicable government security requirements and best practices

• Support Risk Management Framework (RMF) activities throughout the system lifecycle
• Assist with the end-to-end ATO preparation, vulnerability remediation, approval processes, and maintenance
• Develop and regularly update documentation supporting security authorization packages
• Support implementation and assessment of NIST 800-53 security controls
• Work with ISSOs, ISSMs, system owners, security teams, and government Authorizing Officials
• Track security findings and coordinate remediation with engineering teams
• Support Plan of Action and Milestones (POA&M) development and remediation
• Maintain evidence demonstrating security control implementation
• Support continuous monitoring and ongoing authorization activities

• Assess application, infrastructure, network, cloud, and data security risks
• Work with engineering teams to implement secure configuration and deployment practices
• Support vulnerability management and remediation activities
• Evaluate authentication, authorization, identity, access control, encryption, logging, and monitoring mechanisms
• Review system and application configurations for security weaknesses
• Support secure software development and Dev Sec Ops  practices
• Help establish security requirements for APIs, integrations, data pipelines, and AI systems
• Analyze security…