Job location
: Columbus, OH or Nashville, TN (both locations would be for on site work)

We are seeking a Senior Developer with strong expertise in
IBM z/OS Connect
to support Gigawatt.ai modernization initiatives by designing and building new z/OS-based services integrated with MACSS (legacy utility management mainframe application). This role focuses on exposing mainframe capabilities as modern APIs and enabling seamless enterprise integration.

Key Responsibilities
:

• 
  Design, develop, and deploy RESTful APIs using
  IBM z/OS Connect
• 
  Build and expose mainframe services (CICS, IMS, DB2) to distributed systems
• 
  Integrate z/OS services with
  MACSS
  and other enterprise platforms
• 
  Translate business requirements into scalable API-based solutions
• 
  Ensure performance, security, and reliability of z/OS services
• 
  Collaborate with cross-functional teams (middleware, integration, application teams)
• 
  Troubleshoot and resolve issues across z/OS and API layers
• 
  Support modernization initiatives by enabling API-driven mainframe access

Requirements

• 
  Strong hands-on experience with
  IBM z/OS Connect (EE preferred)
• 
  Solid background in
  z/OS environment
  (CICS, IMS, DB2)
• 
  Experience building and consuming
  REST APIs
• 
  Knowledge of
  JSON, OpenAPI/Swagger
• 
  Familiarity with
  mainframe integration patterns
• 
  Strong debugging and performance tuning skills on z/OS
• 
  Experience working in enterprise, high-availability environments

Nice to Have:

• 
  Experience with
  API management tools
  (e.g., IBM API Connect)
• 
  Exposure to
  middleware/integration platforms
• 
  Understanding of
  security protocols
  (OAuth, JWT, RACF)
• 
  Prior experience with
  legacy system modernization initiatives