Senior z/TPF Software Engineer (HLASM)

Job Description

Job Description

Job Title: Senior z/TPF Software Engineer (HLASM)
Location: Washington, DC (On-site)
Employment Type: Contract (W2 through ZipStaff — No C2C or 1099)

About the Opportunity:

ZipStaff is seeking a Senior IBM z/TPF Software Engineer to support mission-critical, high-volume transaction systems at a major national passenger transportation organization.

This is a hands-on senior engineering role. You will design, maintain, and support z/TPF applications written in High-Level Assembler (HLASM), perform deep production diagnostics, and deliver production-safe fixes across inventory, reservation, availability, and ticketing workflows. You will operate as a technical SME with architects, developers, and business analysts to keep these systems stable and performant.

What You’ll Do:

• Design, develop, maintain, and support complex IBM z/TPF applications in HLASM / ASM.
• Analyze, debug, and resolve high-priority production issues using the IBM z/TPF Toolkit, debuggers, dump analysis, and diagnostic utilities.
• Perform low-level troubleshooting of ECB processing, registers, storage management, work areas, control blocks, masks, flags, and transaction execution flows.
• Maintain TPFDF record structures, ordinals, file retrieval/update logic, chain records, and database access paths.
• Trace macro-expanded execution paths and investigate functional logic across multiple processing paths.
• Conduct root-cause and impact analysis for inventory, availability, reservation, and ticketing issues; implement production-safe code fixes.
• Perform peer code reviews, mentor developers, and translate complex business requirements into technical solutions.
• Produce design specs, debugging reports, and technical documentation; support deployments, testing, and post-release validation.

Required Qualifications:

• Bachelor’s degree in Computer Science, Information Systems, Engineering, or equivalent practical experience.
• 8+ years of hands-on IBM z/TPF development, maintenance, and troubleshooting.
• 8+ years of High-Level Assembler (HLASM / ASM) on z/TPF.
• Deep experience with ECB processing, ECB work areas, registers, storage management, and transaction-processing architecture
• Proven use of IBM z/TPF Toolkit, debuggers, dump analysis, and diagnostic utilities on production incidents.
• Experience with high-volume transaction systems (inventory, reservation, availability, ticketing, transportation, airline, or logistics).
• Proficiency with source control and change management (Git, Jira) and Agile / Scrum.
• Ability to independently trace multi-module assembler issues.
• Ability to work on-site in Washington, DC.
• Must be legally authorized to work in the United States without sponsorship now or in the future.

Preferred Qualifications:

• TPFDF record structures, ordinals, file addressing, and chain-record processing.
• C and C/Assembler integration on z/TPF.
• Familiarity with z/OS, TSO/ISPF, JCL, and performance analysis utilities.
• Experience modernizing or optimizing large legacy assembler codebases for high-volume transactions.

About ZipStaff:

ZipStaff partners with leading organizations to connect skilled technology professionals with high-impact contract opportunities. We focus on quality matches, clear communication, and long-term success for candidates and clients.

To apply, submit your resume highlighting hands-on IBM z/TPF, HLASM, production dump analysis, and high-volume transaction-system work.