IT Security & Systems Engineer in Milwaukee, Wisconsin at S3 AeroDefense LLC

Purpose of the Job:

The IT Security & Systems Engineer is responsible for the design, implementation, and governance of enterprise IT infrastructure and security architecture. This role exercises independent judgment and discretion in determining system design, security controls, and technical solutions that protect organizational data and operations.

The position serves as the technical authority for IT systems and security, while also acting as a Tier 3 escalation resource for complex technical issues.

Reports to: IT System Infrastructure Manager

Duties and Responsibilities:

Security Architecture & Compliance (Core Duty)

• Designs, implements, and continuously improves information security architecture aligned with recognized frameworks (e.g., NIST, CMMC)
• Conducts risk assessments and determines appropriate mitigation strategies
• Defines and enforces security controls, standards, and technical policies
• Leads audit readiness efforts and ensures effectiveness of security controls

Systems & Infrastructure Design

• Designs and governs enterprise IT infrastructure, including cloud and on-premise environments (M365, Azure, Active Directory, Intune, etc.)
• Determines system architecture, integration approaches, and technical configurations
• Evaluates and selects technologies, tools, and vendors based on business and security requirements
• Leads implementation of new systems and major upgrades

Network & Firewall Governance

• Designs network security architecture, including segmentation and access control models
• Reviews, approves, and governs firewall rule design and changes based on risk and business need
• Ensures appropriate controls for external access, data transmission, and system exposure

Decision-Making & Technical Authority

• Exercises independent judgment in determining technical solutions and resolving complex system and security issues
• Approves system configurations, access models, and security design decisions
• Provides expert guidance to leadership on IT risk, system performance, and security posture

Advanced Technical Escalation (Tier 3 Support)

• Serves as escalation point for complex or high-risk technical issues
• Diagnoses root causes and implements long-term, systemic solutions rather than temporary fixes
• Identifies trends in incidents and implements improvements to reduce recurring issues

Governance, Documentation & Continuous Improvement

• Establishes and maintains technical standards, procedures, and documentation
• Drives automation and process improvements to enhance security and operational efficiency
• Monitors evolving threats, vulnerabilities, and regulatory requirements and adapts systems accordingly

Scope of Work Allocation (Compliance Guardrail)

• Security architecture, systems design, and decision-making: 50–70%
• System implementation leadership: 20–30%
• Advanced technical support (Tier 3 escalation only): =20–25%

Supervisory Responsibility

This position does not have direct reports but functions as a technical lead and decision authority within the IT environment.

• Associate’s degree plus 3-4 years of experience
• Strong expertise in IT infrastructure, cloud environments, and security frameworks
• Demonstrated experience in systems design, architecture, or engineering roles
• Ability to independently assess risk and determine technical solutions
• Advanced troubleshooting skills with ability to resolve complex system issues