Senior Mainframe Developer

We are seeking an experienced Senior Mainframe Developer with deep expertise in I/O configuration management to support our IBM Z environment.

This role involves hands‑on configuration delivery, ensuring environment stability, and implementing project‑based infrastructure changes.

• Configure and manage mainframe I/O definitions using Hardware Configuration Definition (HCD).
• Generate and implement IOCDS images and coordinate activations across logical partitions.
• Analyze and update existing configurations to support hardware changes, migrations, and upgrades.
• Troubleshoot I/O pathing, device connectivity, and configuration discrepancies.
• Collaborate with internal teams (z/OS systems, storage, network, hardware engineering) to ensure alignment between logical and physical configurations.
• Maintain accurate configuration documentation and provide knowledge transfer to permanent staff.

• Minimum of 5 years of experience defining and maintaining I/O configurations for IBM z/OS systems.
• Proficient in building and managing IOCDS datasets using HCD and IOCP tools.
• Strong knowledge of IBM z/OS operating system internals.
• Hands‑on experience with POR (Power‑On Reset) configuration activations and system startups.
• Expertise in troubleshooting and resolving complex I/O configuration issues.
• Familiarity with channel paths, control units, and device definitions.
• Excellent documentation and communication skills.
• Knowledge of Sysplex configurations and dynamic I/O reconfiguration.
• Experience in capacity planning and hardware upgrades.
• Familiarity with disaster recovery planning for I/O configurations.