Mainframe zTPF Developer Senior

Design, develop, maintain, and support complex IBM z/TPF applications written in High-Level Assembler (HLASM/ASM).

Analyze, debug, and resolve complex production issues across multiple assembler modules, macros, utilities, and transaction-processing flows.

Perform deep root-cause analysis of application, inventory, availability, reservation, and ticketing system issues.

Troubleshoot z/TPF applications using IBM z/TPF Toolkit, debugger, and diagnostic utilities.

Debug ECB (Entry Control Block) processing, registers, storage management, work areas, control blocks, masks, flags, and transaction execution flows.

Analyze and maintain TPFDF record structures, ordinals, file retrieval/update logic, chain records, and database access paths.

Investigate application behavior across multiple processing paths and identify functional differences within assembler-based business logic.

Analyze assembler macros and trace underlying execution flows generated by macro expansion.

Perform impact analysis and implement production-safe fixes for mission-critical applications.

Conduct code reviews and provide technical guidance to development teams.

Collaborate with architects, business analysts, and development teams to understand requirements and implement solutions.

Create and maintain technical documentation, design specifications, debugging findings, and root-cause analysis reports.

Support testing, deployment, production releases, and post-implementation validation activities.

Bachelor's degree in Computer Science, Information Systems, Engineering, or related field, or equivalent practical experience.

8+ years of hands-on experience with IBM z/TPF application development.

8+ years of High-Level Assembler (HLASM/ASM) programming experience.

Strong experience developing, maintaining, and supporting enterprise transaction-processing applications in z/TPF environments.

Expert-level debugging and troubleshooting experience in complex assembler applications.

Hands-on experience with IBM z/TPF Toolkit, debugger, dump analysis, and diagnostic utilities.

Strong experience with ECB (Entry Control Block) processing, ECB work areas, registers, storage management, and transaction execution flows.

Strong experience analyzing and debugging assembler macros and tracing generated execution paths.

Experience performing root-cause analysis across multiple assembler modules, utilities, services, and transaction-processing flows.

Experience investigating and resolving complex production issues in mission-critical systems.

Strong knowledge of inventory, reservation, availability, ticketing, transportation, airline, railroad, or similar transaction-processing applications.

Experience working with z/TPF transaction-processing architecture and system internals.

Experience analyzing application performance and implementing production-safe solutions.

Proficiency with source-control and change-management tools such as Git, Jira, and related enterprise development tools.

Experience supporting production releases, application deployments, and post-implementation validation.

Strong analytical, troubleshooting, problem-solving, communication, and collaboration skills.

Ability to independently investigate, trace, debug, and resolve complex issues spanning multiple assembler modules and processing paths.

Experience working in Agile/Scrum development environments.

Experience with transportation, logistics, reservation, inventory, availability, ticketing, or other transaction-processing systems.

Knowledge of z/OS, TSO/ISPF, JCL, and related mainframe development tools.

Experience with IBM z/TPF Toolkit, dump analysis, debugging utilities, and performance analysis tools.

Experience working with TPFDF record structures, ordinals, file addressing, and chain record processing.

Working knowledge of C programming language and C/Assembler integration in z/TPF environments.

Experience analyzing and modernizing large legacy assembler code bases.

Experience designing, troubleshooting, and optimizing high-volume transaction-processing applications.

About IDEXCEL, INC
Idexcel is an IT services organization, with a mission to bring great people and great organizations together. Our diverse client base represents a wide range of industries, including technology, telecom, insurance, healthcare, manufacturing, banking & financial services, food & commodities trading and federal organizations. Our teams of experienced recruiters directly work with client companies seeking exceptional people to help with their business initiatives. Idexcel, Inc. is an Equal Opportunity Employer. Qualified applicants will receive consideration for employment without regard to race, color, religion, sex, age, disability, military status, national origin or any other characteristic protected under federal, state, or applicable local law.