EY - GDS Consulting - Mainframe Modernization- GEN AI - Senior

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AIA – Mainframe Modernization Specialist   The opportunity   We are seeking a skilled Senior Mainframe Modernization Specialist to join our AI-Driven Modernization practice, focused on transforming legacy mainframe systems into agile, efficient, and cloud-ready platforms. The ideal candidate will bring a strong blend of mainframe expertise, AI tools proficiency, and cloud technologies along with hands-on collaboration with cross-functional teams to deliver scalable modernization outcomes.   You will work closely with technology leads, architects, and business stakeholders to analyse legacy applications, leverage AI/ML to automate code analysis and refactoring, and execute migration of mainframe workloads to modern distributed and cloud-native platforms.     Your key responsibilities   Technical Excellence:

Mainframe Systems Analysis and Understanding

Assess and analyse existing mainframe applications (COBOL, JCL, VSAM, DB2, CICS, IMS) to identify modernization opportunities and dependencies. Document current-state architecture, data flows, batch schedules, and integration points across legacy ecosystem components. Perform impact analysis and complexity assessment for potential transitions to modern platforms.

AI-Driven Mainframe Modernization

Apply AI tools and custom AI agentic workflows for automated code analysis, refactoring, and technical debt reduction. Develop and fine-tune AI-powered assistants to accelerate system conversion and code translation (e.g., COBOL to Java/Python). Apply prompt engineering and context engineering techniques to maximise accuracy and efficiency of LLM-driven modernization workflows.

Modernization Execution

Execute modernization tasks including rehosting, refactoring, or rebuilding mainframe workloads based on defined strategies. Participate in the design and implementation of target-state architectures aligned with cloud-native and microservices patterns. Ensure code quality, testability, and maintainability throughout the modernization lifecycle.

API and Microservices Development

Contribute to the design and development of API integrations and microservices to replace or wrap legacy mainframe functionality. Implement RESTful APIs, event-driven architectures, and integration patterns as part of the target-state solution.

Cloud and Platform Integration

Support migration of mainframe workloads to cloud platforms (AWS, Azure, Google Cloud) using AI-driven solutions. Integrate modernized components with cloud-native services, containerised workloads (Docker, Kubernetes), and CI/CD pipelines. Familiarity with infrastructure-as-code, observability, and security best practices for modernized workloads.

Documentation and Reporting

Create and maintain technical documentation including system designs, migration runbooks, and AI pipeline configurations. Provide regular status updates on modernization progress, risks, and deliverables to project leads.

Skills and Attributes:   Educational Background

B.Tech / B.E. / MCA / M.Tech or equivalent degree in Computer Science, Information Technology, or a related field.

Professional Experience

5 to 9 years of hands-on experience with legacy mainframe systems (COBOL, JCL, Assembler, CICS, DB2, IMS, VSAM). Experience with data migration, integration, ETL processes, and at least one major cloud platform (AWS, Azure, or Google Cloud). Proficiency in programming/scripting languages such as Python and/or Java. Working knowledge of APIs, microservices architecture, and containerization tools (Docker, Kubernetes). Hands-on experience with