Mainframe Assembler Jobs (NOW HIRING)

Job#: 3044629
Job Description:
Mainframe Assembler Developer
Location: Addison, TX/ Charlotte NC (Hybrid)
Duration: 12 months
Role Overview
We are seeking a highly experienced Mainframe Assembler Developer to support and enhance a mission-critical legacy application written in IBM z/OS assembler language. This role requires a self-sufficient engineer capable of independently analyzing, maintaining, and improving high-volume, high-availability batch processing systems in a regulated financial services environment. The ideal candidate brings deep expertise across core mainframe technologies and strong familiarity with parallel sysplex environments.
Key Responsibilities

• Analyze, maintain, and improve high-volume, high-availability batch processing systems.
• Provide production support for IBM Mainframe applications.
• Develop and troubleshoot JCL.
• Manage GDGs and batch processing to meet strict SLAs.
• Work independently within loosely documented legacy environments.
• Analyze complex assembler codebases to diagnose and resolve critical production issues.
• Handle incident management using tools like ServiceNow or Remedy.

Required Qualifications
Experience: 8+ years of experience in IBM Mainframe application development and production support.
Technical Skills:

• Assembler (HLASM) programming
• JCL/ECL development and troubleshooting
• TSO / ISPF environment
• Connect:Direct (NDM)
• ISPW (or equivalent change management tools)
• CA7 scheduling
• GitHub CoPilot
• Mainframe datasets, VSAM, and utilities

Professional Skills:

• Experience supporting high-volume financial transaction systems and production batch environments with strict SLAs.
• Experience working in high-availability environments, including Sysplex architectures and multiple LPARs.
• Understanding of production support processes and incident management.

Preferred Qualifications

• Experience in financial services or banking environments.
• Prior experience with check processing, image item processing, or payment processing platforms.
• Familiarity with SMP/E for system maintenance and upgrades.
• Familiarity with SAR (System Activity Reporter / reporting tools).
• Experience supporting assembler applications during platform upgrades or macro changes.

Everforth Apex is a world-class IT services company that serves thousands of clients across the globe. When you join Everforth Apex, you become part of a team that values innovation, collaboration, and continuous learning. We offer quality career resources, training, certifications, development opportunities, and a comprehensive benefits package. Our commitment to excellence is reflected in many awards, including ClearlyRateds Best of Staffing in Talent Satisfaction in the United States and Great Place to Work in the United Kingdom and Mexico.
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Everforth Apex Benefits Overview: Everforth Apex offers a range of supplemental benefits, including medical, dental, vision, life, disability, and other insurance plans that offer an optional layer of financial protection. We offer an ESPP (employee stock purchase program) and a 401K program which allows you to contribute typically within 30 days of starting, with a company match after 12 months of tenure. Everforth Apex also offers a HSA (Health Savings Account on the HDHP plan), a SupportLinc Employee Assistance Program (EAP) with up to 8 free counseling sessions, a corporate discount savings program and other discounts. In terms of professional development, Everforth Apex hosts an on-demand training program, provides access to certification prep and a library of technical and leadership courses/books/seminars once you have 6+ months of tenure, and certification discounts and other perks to associations that include CompTIA and IIBA. Everforth Apex has a dedicated customer service team for our Consultants that can address questions around benefits and other resources, as well as a certified Career Coach. You can access a full list of our benefits, programs, support teams and resources within our 'Welcome Packet' as well, which an Everforth Apex team member can provide.
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