Job Description
Senior System Engineer (Email Security)
Washington, DC - 100% ONSITE
Compensation: W2 or C2C
Per Federal contract U.S. Citizenship Required
Security Clearance: Must be able to pass Federal background check
Application Deadline: 9/11/2026
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, and its subsidiaries including Joulé and Mountain Ltd., are leaders in delivering outsourced services and workforce solutions across North America. We help clients get work done more efficiently and economically, without compromising quality. System One not only serves as a valued partner for our clients, but we offer eligible employees health and welfare benefits coverage options including medical, dental, vision, spending accounts, life insurance, voluntary plans, as well as participation in a 401(k) plan.
System One is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex (including pregnancy, childbirth, or related medical conditions), sexual orientation, gender identity, age, national origin, disability, family care or medical leave status, genetic information, veteran status, marital status, or any other characteristic protected by applicable federal, state, or local law.
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Numbers & Facts
| Location | Washington, DC |
| Industry | Staffing/Employment Agencies |
| Company Size | 2,500 to 4,999 employees |
| Website | https://systemone.com |
About Company
Every day, System One focuses on services and solutions that require a high degree of specialization, in-demand technical skills, and large-scale operational expertise. We are essential partners to those on the front lines of our nation’s most critical infrastructure, technology, and life sciences initiatives.
Founded more than 40 years ago as a staffing partner to the engineering industry, today System One is a diversified organization operating in over 50 locations and putting more than 9,000 people to work in the United States, Canada, and the United Kingdom.