Senior Mainframe Application Developer

Posted yesterday

thorivaDenver (CO)

Software DevelopersCustom Computer Programming Services

SENIORITY

Lead

About the role

Senior Mainframe Application Developer Thoriva, an Infinite Company, is seeking a Senior Mainframe Application Developer to support the design, development, enhancement, and maintenance of enterprise mainframe systems supporting mission-critical business operations. This role involves hands-on development across both batch and online mainframe applications, as well as participation in testing, production support, and modernization initiatives. The ideal candidate has deep experience with IBM z/OS environments, strong COBOL development skills, and a solid understanding of mainframe data stores and transaction processing systems.

ABOUT THE COMPANY: Thoriva is an AI technology company delivering intelligent, data-driven solutions to transform government operations. We combine AI solutions, commercial expertise, and complex business logic to address government and federal agencies’ biggest challenges.

JOB SUMMARY: As Senior Mainframe Application Developer, you will bring IBM z/OS expertise to design, develop, and maintain enterprise-grade mainframe applications for mission-critical programs. You will collaborate with cross-functional teams and contribute to modernization efforts. applying AI-enabled tools where applicable to accelerate delivery and documentation.

Key Responsibilities: Design, develop, enhance, and maintain mainframe applications using COBOL.Develop and support batch and online programs (CICS).Write and maintain JCL, manage job scheduling, and support batch cycles. Develop and maintain integrations with DB2, VSAM, and other mainframe data sources. Perform unit testing, system testing, and UAT support. Troubleshoot production issues and provide production support. Participate in requirements analysis and translate business needs into technical solutions. Collaborate with cross-functional teams including analysts, testers, and infrastructure teams. Follow established SDLC, change management, and release processes. Support documentation, knowledge transfer, system modernization initiatives, and continuous improvement as applicable.

Required Qualifications: 10+ years of hands-on mainframe application development experience (flexible for strong candidates).Strong proficiency in COBOL, JCL, DB2, and VSAM.Experience with CICS and/or IMS.Experience developing and supporting both batch and online applications. Familiarity with mainframe development and debugging tools, such as Expeditor, Intertest, Endeavor, or Changeman. Experience working in production support environments. Strong problem-solving, troubleshooting, and communication skills. Ability to work independently with minimal ramp up. Excellent communication skills (written and verbal).

Preferred Qualifications: Financial services or other regulated industry experience. Strong testing background (functional, system, and UAT).Experience in Agile and/or Waterfall delivery environments. Exposure to modernization efforts or integration with web / distributed technologies. Experience using AI tools to support code generation, documentation, test case creation, testing acceleration, and developer productivity. Familiarity with AI-enabled and modernization tools such as Zowe, Git Hub Copilot, and IBM Watsonx. Ability to obtain and maintain a U.S. citizen security clearance, if required for client or federal program support.

Compensation & Benefits: Competitive base salary commensurate with experience and scope of the role Comprehensive benefits package including health, dental, vision, 401(k), and paid time off (PTO)Hybrid work environment with flexibility for remote work and in-person collaboration in Vienna, VASignificant influence over how Thoriva scales its delivery and technology practice, with direct access to senior leadership

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