Senior z/TPF Software Engineer (HLASM)

ZipStaff•Washington, DC

1d•Onsite

About The Position

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.

Requirements

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.

Nice To Haves

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.

Responsibilities

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.