Senior Mainframe Test Lead; z​/VSE to z​/OS Migration

Senior Mainframe Test Lead (z/VSE to z/OS Migration)

NTT DATA's Client is seeking a Senior Mainframe Test Lead (z/VSE to z/OS Migration) to lead the end-to-end testing strategy, planning, governance, and execution for a large-scale z/VSE to z/OS migration program. This role will be responsible for defining the testing approach, ensuring comprehensive coverage across applications, infrastructure, data, security, and operational processes, while providing overall quality and release readiness governance.

The ideal candidate must possess deep Mainframe testing and migration expertise and have prior experience leading testing efforts for Mainframe modernization, platform migration, or legacy transformation programs. A key responsibility of this role is establishing a risk-based testing strategy, ensuring testing effort is aligned to the scope and complexity of changes introduced by the migration rather than applying uniform testing across all components.

• Test Strategy & Governance
• Define and own the overall migration testing strategy, framework, and roadmap.
• Establish testing standards, quality gates, entry/exit criteria, and governance processes.
• Develop a risk-based testing methodology aligned to migration waves and cutover milestones.
• Provide executive reporting on testing progress, quality metrics, risks, and release readiness.
• Risk-Based Testing & Change Impact Assessment
• Lead application and infrastructure impact assessments to understand migration-related changes.
• Establish a risk-ranking model to classify components as High, Medium, or Low Risk based on:
• Code modifications
• JCL conversion impacts
• Data migration changes
• CICS transaction changes
• Interface dependencies
• Security changes
• Operational and scheduler impacts
• Business criticality
• Design testing depth and coverage based on migration risk and business impact.
• Focus testing effort on areas of highest risk while optimizing effort for unchanged components.
• Maintain a Testing Risk Register and Migration Testing Heat Map.
• Identify migration-specific risks and ensure mitigation plans are incorporated into testing activities.
• Test Planning & Design
• Develop comprehensive testing plans covering:
• System Testing
• System Integration Testing (SIT)
• End-to-End Business Process Testing
• Regression Testing
• Data Validation & Reconciliation Testing
• Performance & Volume Testing
• User Acceptance Testing (UAT)
• Cutover & Rollback Validation Testing
• Establish traceability between requirements, migration changes, risks, and test cases.
• Mainframe & Migration Validation
• Define testing coverage for:
• COBOL applications
• CICS transactions
• JCL conversion and batch processing
• VSAM, DB2, and IMS databases
• File transfers and interfaces
• Security configurations and access controls
• Enterprise schedulers
• Infrastructure and operational procedures
• Validate functional equivalence and operational readiness of workloads migrated to z/OS.
• Ensure proper reconciliation of converted data and migrated business processes.
• Federated Test Leadership
• Coordinate testing across:
• Mainframe Teams
• Application Teams
• Infrastructure Teams
• Security Teams
• Database Teams
• Business SMEs
• Establish testing standards and reusable assets across work streams.
• Lead defect triage, prioritization, and remediation activities.
• Drive issue resolution and dependency management across teams.
• Cutover Readiness & Deployment Validation
• Define cutover rehearsal and mock migration testing strategies.
• Validate production deployment procedures and rollback capabilities.
• Ensure all critical business processes are successfully executed during rehearsal events.
• Provide Go/No-Go recommendations for migration releases.

• Mandatory Mainframe Experience
• 10+ years of experience in Test Architecture, Test Management, or Quality Engineering.
• Strong hands-on knowledge of Mainframe applications, platforms, and testing methodologies.

• z/VSE
• z/OS
• COBOL
• CICS
• JCL
• VSAM
• DB2 and/or IMS
• RACF / ACF2 / Top Secret
• Batch Processing
• Enterprise Scheduling tools
• Demonstrated experience leading testing for Mainframe modernization, platform upgrades, rehosting, or z/VSE-to-z/OS migration initiatives.
• Risk-Based Testing Expertise
• Proven experience implementing…