Senior Mainframe zTPF Developer

Senior Mainframe zTPF Developer Location:- Washington – DC (Remote) Candidate must be from EST/CST only.

Client:- Amtrak % Remote :- USC, GC, H4EAD, L2s Position Summary: Client is seeking a highly experienced Senior Mainframe zTPF Developer to design, develop, maintain, troubleshoot, and support mission-critical transaction-processing applications.

This position requires deep expertise in IBM z/TPF, High-Level Assembler, complex production debugging, and high-volume reservation, inventory, availability, or ticketing systems.Key

• Design, develop, maintain, and support complex IBM z/TPF applications written in High-Level Assembler HLASM or ASM.
• Troubleshoot and resolve complex production issues involving multiple assembler modules, macros, utilities, services, and transaction-processing flows.
• Perform detailed root-cause analysis involving inventory, availability, reservation, ticketing, and related transaction-processing systems.
• Use the IBM z/TPF Toolkit, debugger, dump analysis, and diagnostic utilities to investigate application behavior.
• Debug Entry Control Block processing, including ECB work areas, registers, storage management, control blocks, masks, flags, and transaction execution flows.
• Analyze and maintain TPFDF record structures, ordinals, file retrieval and update logic, chain records, and database access paths.
• Examine multiple processing paths to identify functional differences within complex assembler-based business logic.
• Analyze assembler macros and trace the underlying execution paths created through macro expansion.
• Conduct impact assessments and implement safe, reliable fixes within mission-critical production environments.
• Review code and provide technical guidance to developers and other team members.
• Collaborate with architects, business analysts, developers, and stakeholders to translate requirements into effective technical solutions.
• Create and maintain technical documentation, design specifications, debugging findings, and root-cause analysis reports.
• Support testing, deployments, production releases, and post-implementation validation.

Required Qualifications

• Bachelor’s degree in Computer Science, Information Systems, Engineering, or a related field, or equivalent practical experience.
• Eight or more years of hands-on IBM z/TPF application-development experience.
• Eight or more years of High-Level Assembler HLASM or ASM programming experience.
• Advanced experience developing, maintaining, and supporting enterprise transaction-processing applications in a z/TPF environment.
• Expert-level ability to debug and troubleshoot complex assembler applications.
• Hands-on experience with the IBM z/TPF Toolkit, debugger, dump analysis, and related diagnostic utilities.
• Strong knowledge of ECB processing, ECB work areas, registers, storage management, and transaction execution flows.
• Strong experience analyzing assembler macros and tracing generated execution paths.
• Demonstrated ability to perform root-cause analysis across multiple assembler modules, utilities, services, and processing paths.
• Experience resolving complex production issues in high-availability, mission-critical environments.
• Strong knowledge of inventory, reservation, availability, ticketing, transportation, airline, railroad, or comparable transaction-processing applications.
• Strong understanding of z/TPF transaction-processing architecture and system internals.
• Experience analyzing application performance and implementing production-safe solutions.
• Experience with source-control and change-management tools such as Git and Jira.
• Experience supporting production deployments, releases, and post-implementation validation.
• Strong analytical, troubleshooting, communication, and collaboration skills.
• Ability to independently investigate and resolve issues spanning multiple assembler modules and processing paths.
• Experience working in an Agile or Scrum development environment. Preferred Qualifications
• Experience supporting transportation, railroad, airline, logistics, reservation, inventory, availability, or ticketing platforms.
• Knowledge of z/OS, TSO/ISPF, JCL, and related mainframe-development tools.
• Advanced experience with z/TPF dump analysis, debugging utilities, and performance-analysis tools.
• Experience with TPFDF record structures, ordinals, file addressing, and chain-record processing.
• Working knowledge of C programming and C/Assembler integration within a z/TPF environment.
• Experience analyzing or modernizing large legacy assembler codebases.
• Experience designing, troubleshooting, and optimizing high-volume transaction-processing applications.