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David Careers

Mainframe Assembler Developer

Posted 2 days ago

anvetaAddison (TX)
Software DevelopersCustom Computer Programming Services

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About the role

Mainframe Assembler Developer
Location: Hybrid in Addison, TX or Charlotte, NC (3 days in office 2 days remote) Relo candidates are fine
Duration: 12+ Month Contract to hire
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 Service
  • Now or Remedy.
Experience: 5+ years of experience in IBM Mainframe application development and production support.
Technical Skills: Assembler (HLASM) programmingJCL/ECL development and troubleshootingTSO / ISPF environment Connect: Direct (NDM)ISPW (or equivalent change management tools)CA7 scheduling GitHub CoPilot

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