Job Title: Sr. System Engineer (Email Security)
Location: Washington, DC
Type: Contract 9/11/2026- 12/31/2026
Compensation: W2 or C2C
Work Model: 100% Onsite – Full Time onsite
Hours: 40.0 per week
Security Clearance: Must be able to pass Federal background check

Responsibilities:

• Lead the migration from on-premises IronPort email security appliances to Proofpoint cloud-based email security solution, ensuring seamless transition with minimal disruption to email services.
• Design, configure, and maintain Proofpoint as an enterprise service.
• Set Proofpoint firewall rules and maintain block lists; respond to requests to quarantine or release email.
• Deep understanding of MTA and Proofpoint Messaging Security Gateway and Proofpoint Messaging Security Gateway 8.x.
• Work with Linux Server and VMWare environments to support migration efforts and ongoing system integrity.

Requirements:

• Expert level experience designing, configuring, and maintaining Proofpoint as an enterprise service.
• Experience in setting Proofpoint firewall rules and maintaining block lists; responding to requests to quarantine or release email.
• Deep understanding of MTA and Proofpoint Messaging Security Gateway and Proofpoint Messaging Security Gateway 8.x.
• Experience with Linux Server and VMWare environments.

System One is a leading provider of specialized, highly technical services and solutions to critical infrastructure, technology, life sciences, and government sectors. We partner with large private and public organizations who trust us to execute their complex, mission-critical initiatives through our outsourced services and workforce solutions.