Senior Software Engineer – Mainframe

Senior-level mainframe engineer responsible for delivering secure, resilient, and maintainable enterprise application solutions across delivery, modernization, and production support. This role partners across business, technology, QA, architecture, and operations to deliver quality outcomes aligned to enterprise SDLC, risk, regulatory, and technology standards. 

Primary Responsibilities 

1. Mainframe Software Engineering & Delivery 

• Own delivery of secure, resilient, performance-aware mainframe solutions across the full lifecycle from analysis and design through implementation, validation, and production support. 

• Translate business and technical requirements into quality application changes that support reliable batch, online, interface, and data-processing capabilities. 

• Troubleshoot application, transaction, batch, interface, data flow, restart/recovery, and downstream impact issues. 

• Prepare technical specifications, implementation and backout plans, support documentation, and delivery estimates with clear ownership of risks, dependencies, quality, and production stability. 

2. SDLC, Quality & Release Readiness 

• Execute SDLC activities across requirements analysis, estimation, design, coding, testing, documentation, change control, and release readiness. 

• Apply GitLab and DevOps practices for source control, branching, merge requests, peer review, traceability, CI/CD, deployment planning, and implementation validation. 

• Prepare and execute unit, integration, regression, batch validation, data reconciliation, UAT support, production verification, and defect resolution activities. 

• Improve reliability and delivery quality through peer review, code quality, test coverage, automation, release evidence, and post-production validation. 

3. Modernization, Integration & Stability 

• Support modernization initiatives including API enablement, data integration, technical debt reduction, platform resiliency, and modern IBM z development practices. 

• Contribute to integration designs across mainframe, distributed platforms, cloud-connected applications, MQ, APIs, and data movement patterns. 

• Support production applications, batch schedules, online transactions, interfaces, operational workflows, incident resolution, root cause analysis, and problem management. 

• Improve application stability, performance, restartability, supportability, operational efficiency, and recovery readiness. 

4. Collaboration & Technical Leadership 

• Partner with business, product, architecture, QA, operations, and engineering teams to deliver reliable solutions. 

• Guide less experienced engineers on application functionality, coding, debugging, testing, release procedures, and SDLC adherence. 

• Maintain strong knowledge of supported applications, business processes, dependencies, operational impacts, and technical risks. 

Scope of Responsibility 

• Works independently on complex technical assignments with guidance from the Technology Team Lead, Engineering Lead, or Architect. 

• Coordinates small to medium technical work efforts and provides technical guidance to less experienced engineers as needed. 

• Escalates technical risks, delivery issues, design gaps, control concerns, and operational impacts appropriately. 

Education Required 

• Associate’s degree and a minimum of 5 years of systems analysis and/or application development experience; or 

• In lieu of a degree, a combined minimum of 7 years of higher education and/or work experience, including a minimum of 5 years of systems analysis and/or application development experience. 

Required Experience  

• IBM z/OS mainframe application development experience with COBOL, CICS, JCL, DB2 for z/OS, VSAM, TSO/ISPF, SDSF, Easytrieve+, and related tools supporting batch, online, interface, and data-processing workloads. 

• Strong technical depth in batch and online processing, including job stream analysis, restartability, scheduling dependencies, ABEND resolution, CICS transaction troubleshooting, and production impact assessment. 

• Experience with DB2 SQL, data validation, reconciliation, copybooks/file layouts, interface analysis, and performance-oriented troubleshooting. 

• Working knowledge of modern IBM z development practices and tools such as IDz, ADDI, DBB, ZUnit, z/OS Connect, ZDIH, and mainframe debugging tools including File-AID, Abend-AID, Xpediter, InterTest, or equivalent. 

• GitLab, source control, code review, release management, change control, CI/CD, traceability, and deployment readiness experience. 

• SDLC and Agile delivery experience including requirements analysis, story refinement, estimation, design, coding, unit testing, regression support, implementation, production verification, documentation, and tools such as Jira, Zephyr, and ServiceNow. 

• Strong analytical, debugging, problem-solving, communication, and collaboration skills across business, technology, QA, architecture, operations, Agile, and cross-functional teams. 

• Ability to work independently, assess impact across programs, interfaces, data flows, batch processes, and connected applications, and escalate risks, dependencies, design gaps, and operational concerns appropriately. 

Preferred Experience  

• Experience supporting banking, lending, payments, servicing, or other regulated enterprise applications. 

• Experience with modernization, platform migration, API enablement, z/OS Connect implementation, MQ/service integration, distributed platform connectivity, technical debt reduction, resiliency, or release quality initiatives. 

• Experience with Sonar or equivalent code quality/static analysis tools, automated testing, regression automation, deployment validation, observability, monitoring, and operational dashboards. 

• Familiarity with RACF or mainframe security concepts, disaster recovery, recovery validation, audit evidence, risk, regulatory, and internal control expectations. 

• Experience applying AI-assisted engineering tools for code analysis, documentation, testing, or operational support with appropriate human review and validation.