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Assembler Developer

Posted today

software technologyBethesda (MD)

SENIORITY

Lead

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About the role

Assembly Language Developer We are seeking a highly experienced Assembly Language Developer with deep expertise in IBM z/OS mainframe environments, IRS Core Record Layouts (CRL), and legacy system modernization. The ideal candidate will support the extraction of business rules from legacy code, assist in code conversion to modern platforms, and work with mission-critical IRS systems such as the Individual Master File (IMF) and Business Master File (BMF).
Key Responsibilities:
  • Analyze, maintain, and enhance legacy code written in IBM z/OS assembly language.
  • Extract business rules from existing assembly code and assist in code conversion efforts.
  • Work with IRS Core Record Layouts (CRL) and QSAM data formats to support data processing and transformation.
  • Collaborate with cross-functional teams to ensure accurate interpretation and migration of legacy logic.
  • Utilize CA Endevor Software Change Manager (SCM) for version control, release management, and secure code handling.
  • Leverage BMC Control-M for job scheduling, workflow automation, and monitoring batch job execution.
  • Required Skills/Level of Experience:
  • Bachelor’s degree in Computer Science, Information Systems, or a related field.
  • In-depth knowledge of IBM z/OS assembly language, including:
  • Assembly instructions, addressing modes, and data manipulation techniques
  • Job control processing and JCLFamiliarity with IBM mainframe architecture, including:
  • Storage hierarchy (registers, memory, I/O)
  • System calls (SVCs) and interrupt handling
  • Experience with IRS Core Record Layouts (CRL) and QSAM/VSAM data formats (highly desirable).Experience with IRS IMF or BMF systems (highly desirable).Proficiency with CA Endevor SCM for secure and controlled software development lifecycle management.
  • Experience with BMC Control-M for job automation and workflow orchestration.
  • Strong understanding of mainframe development tools, including debuggers, assemblers, linkers, and utilities.
  • Familiarity with DB2 and other legacy data storage formats.

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