Application Programming Interface (API), Artificial Intelligence (AI), Banking Services, Cobol Programming Language, Consulting, Debugging Skills, IBM CICS (Customer Information Control System), IBM DB2, IBM z-OS Operating System, Identify Issues, Insurance, JCL (Job Control Language), Mainframe Computer, Problem Solving Skills, Production Support, Production Systems, Software Administration, Software Development, Systems Scalability
ITTConnect is seeking a Senior Mainframe Developer (zOS Environment) to work on site for a client in the Columbus, OH area. This is a contract position with a client that is a global leader in consulting, digital transformation, technology and engineering services with over 300,000 team members in nearly 50 countries. The end client is in the Utilities sector.
Job location: Columbus, OH or Nashville, TN (both locations would be for on site work)
We are seeking a Senior Mainframe Developer to support a critical legacy platform (MACSS) as part of a large-scale modernization initiative tied to the adoption of the Gigawatt AI platform.
This role sits at the intersection of legacy system stability and modern platform enablement, where core mainframe applications are being API-enabled and integrated into an AI-driven utility platform. You will play a key role in ensuring that foundational systems are scalable, reliable, and ready to support real-time data access and service exposure.
Key Responsibilities:
- Own and support a core mainframe application (MACSS) across production, enhancements, and project initiatives
- Develop and maintain applications using COBOL, JCL, DB2, and CICS
- Troubleshoot and resolve production issues across batch and online systems
- Collaborate with API and platform teams to enable integration via z/OS Connect services
- Support data flows and service exposure to downstream platforms (APIM, Kafka, etc.)
- Participate in system design discussions to support modernization and integration efforts
- Ensure performance, reliability, and scalability of legacy systems
Why This Role Matters
This position is critical in enabling the organizationâs transition to a modern, API-driven architecture by ensuring the stability and scalability of its core legacy systems.
Requirements
- 8+ years of hands-on mainframe development experience
- âStrong expertise in:
- Proven experience supporting production systems and critical applications
- Experience working in large enterprise environments (preferably utilities, banking, or insurance)
- Strong debugging and problem-solving skills in complex legacy environments
Preferred Qualifications:
- Utilities industry experience.
- Experience with IBM z/OS Connect
- Exposure to API enablement of mainframe systems
- Familiarity with event-driven architectures (Kafka or similar)
- Experience supporting systems undergoing modernization or digital transformation.