Senior System Engineer (IBM Mainframe)

Overview TISTA Science and Technology is seeking a Senior System Engineer to join our growing team. At TISTA, you’ll do meaningful, mission‑driven work that improves lives alongside teammates you trust and leaders who are transparent and supportive. We invest in your learning and internal mobility so you can build a career that keeps advancing. We’re proud to serve and hire Veterans, and we put people first in everything we do. TISTA associates enjoy above Industry Healthcare Benefits, Remote Working Options, Paid Time Off, Training/Certification opportunities, Healthcare Savings Account & Flexible Savings Account, Paid Life Insurance, Short-term & Long-term Disability, 401K Match, Professional development reimbursement, Employee Assistance Program, Paid Holidays, Military Leave, and much more! Responsibilities Install, configure, and maintain IBM mainframe operating systems, including IBM z/OS. Perform installation, upgrades, and maintenance of ISV (Independent Software Vendor) products using tools such as SMP/E. Customize system parameters, libraries, and subsystems to meet organizational requirements. Apply maintenance (PTFs, APARs) and perform system IPL planning and execution Troubleshoot system issues, analyze dumps, and resolve software-related problems. Support storage management processes including DASD, SMS, and DFSMS. Maintain documentation for system configurations, procedures, and changes. Collaborate with application teams, operations, and vendors for pr