Senior Java Developer, Mainframe Modernization

We are seeking aSenior Java Developer to join an AWS ProServe mainframe modernization engagement. This initiative transforms legacy COBOL/JCL business logic into cloud-native Java microservices, leveraging agentic AI capabilities to accelerate code generation and ensure functional equivalence with source systems.

Responsibilities

• Transform decomposed mainframe business logic from COBOL and JCL into cloud-native Java microservices using Spring Boot and modern architectural patterns
• Leverage agentic AI tools to generate microservice specifications, modernized application code, and Infrastructure as Code from reverse-engineered mainframe components
• Validate AI-generated output for functional equivalence against original mainframe logic, identify and resolve transformation gaps
• Review and refine mappings between mainframe constructs and target Java microservice implementations to preserve business logic
• Collaborate with architects to refine microservice designs, optimize service boundaries, and implement appropriate API contracts
• Document transformation decisions, architectural patterns, and integration specifications to support knowledge transfer and maintenance

Requirements

• 5+ years of experience in Java development with advanced expertise in Spring Boot
• Advanced skills in microservice architecture style
• Proficiency in AWS Mainframe Modernization services and application modernization
• Reading comprehension of COBOL, JCL, and VSAM file structures
• Familiarity with CICS transaction processing on IBM Mainframe
• Proficiency in English at a B2+ level

Nice to have

• Understanding of cloud-native development patterns
• Knowledge of AWS Transform
• Background in Kiro and AI-assisted development tools