Job Description

We are seeking a highly experienced Senior Mainframe Reverse Engineering Lead to support a large-scale AWS Transformation initiative focused on modernizing legacy mainframe applications and data processing systems. The role will be responsible for analyzing existing mainframe applications, documenting business rules and technical processes, and supporting the migration of applications and data to modern cloud-based platforms.

The successful candidate will perform detailed analysis of COBOL programs, JCL workflows, DB2 databases, VSAM files, batch processing jobs, interfaces, and data transformation logic. Working closely with business SMEs, developers, cloud engineers, and program leadership, this individual will identify and document application functionality, business processes, data flows, system dependencies, and integration points embedded within legacy systems.

Key responsibilities include reverse engineering complex applications, creating technical and functional documentation, developing source-to-target mappings, identifying modernization opportunities, and supporting application migration strategies. The role will also leverage AI-assisted analysis and modernization tools to accelerate discovery and improve the quality of transformation artifacts.

The Senior Mainframe Reverse Engineering Lead will provide technical leadership throughout the discovery and modernization lifecycle, help identify risks and dependencies, and ensure that modernization efforts preserve critical business functionality while enabling migration to AWS and modern data platforms.

Required Qualifications

• Bachelor's degree in Computer Science, Information Systems, Engineering, or related field.
• 15+ years of overall IT experience.
• 10+ years of hands-on IBM Mainframe experience.
• Strong expertise in COBOL, JCL, DB2, VSAM, CICS, and mainframe batch processing.
• Proven experience performing application discovery, reverse engineering, and legacy system analysis.
• Experience identifying and documenting business rules, technical logic, and application dependencies.
• Strong understanding of data mapping, data transformation, and system integration concepts.
• Experience in creating functional specifications, technical documentation, process flows, and dependency diagrams.
• Excellent analytical, troubleshooting, and communication skills.
• Ability to lead discovery and modernization workstreams independently.
• Experience leveraging GenAI or AI-assisted code analysis and reverse engineering tools.

Preferred Qualifications

• Experience with AWS Mainframe Modernization, AWS Transform services, or similar modernization platforms.
• Experience supporting large-scale cloud migration and application modernization initiatives.
• Knowledge of AWS services including S3, Lambda, Glue, ECS/EKS, and RDS.
• Experience with Java, Spring Boot, Python, Spark/PySpark, Airflow, Iceberg, or Cloudera platforms.
• Healthcare, Medicaid, Claims Processing, Insurance, or Financial Services industry experience.
• Experience working with both onshore and offshore teams.
• AWS, TOGAF, or other relevant technical certifications preferred.

Additional Information

At Tieto, we believe in the power of diversity, equity, and inclusion. We encourage applicants of all backgrounds, genders (m/f/d), and walks of life to join our team, as we believe that this fosters an inspiring workplace and fuels innovation. Our commitment to openness, trust, and diversity is at the heart of our mission to create digital futures that benefit businesses, societies, and humanity.

Diversity, equity and inclusion | Sustainability | Tieto

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