Senior Backend Developer – Java, Spring Batch, Modernización Mainframe, IA Aplicada al SDLC

This is a fully remote position, open to applicants in Spain.

📋 Description

• Analyze COBOL programs and JCL flows, understanding dependencies, functional logic, and batch processes.

• Design and implement target architectures based on Java, Spring Boot, and Spring Batch.

• Define Jobs, Steps, Readers & Writers, Chunk Processing, restart strategies, error management, and return codes.

• Develop and maintain specifications using Spec-Driven Development approaches.

• Build and optimize AI agents and automation applied to development, including Claude Code, Cursor, and GitHub Copilot Agents.

• Implement validation mechanisms and functional equivalence between legacy systems and modernized solutions.

• Design and execute testing strategies, including Golden Master, Mutation Testing, regression testing, and result comparison.

• Analyze quality metrics, productivity, and cost of the development pipeline.

• Propose continuous improvements in architecture, automation, and quality.

• Participate in a strategic technological modernization project and in the construction of tools and AI agents applied to the SDLC.

⛳️ Requirements

• More than 5 years of experience in Java development.

• Strong experience with Spring Core, Spring Boot, Spring Data, and Spring Batch.

• Production experience with complex batch processes, large data volumes, reprocessing, and fault tolerance.

• Knowledge of batch architectures, system integration, and file processing.

• Ability to analyze COBOL, JCL, Copybooks, and embedded SQL.

• Experience applying AI to the development cycle: Prompt Engineering, AI agents, evaluating responses from LLMs, and controlling hallucinations.

• Advanced testing experience: Mutation Testing, test automation, boundary cases, and oracle design.

• Proficiency in Git Bash and Python.

• Comfort working in terminal and advanced technical environments.

• Professional English is a plus.

• Experience in Mainframe banking environments: z/OS, DB2, CICS, IMS, and Control-M is desirable.

• Experience in COBOL to Java migrations and modernizing legacy applications is a plus.

• Knowledge of Spec-Driven Development and executable specifications is a plus.

• Experience with corporate batch frameworks, APX, Elara, and proprietary banking frameworks is a plus.

• Experience building pipelines with MCP, Hooks, Subagents, and Quality Gates is a plus.

• Experience measuring cost metrics per token, generation quality, and AI-assisted productivity is a plus.

🏝️ Benefits

• 23 vacation days per year.

• 14 payments: 12 monthly and two extras (June and December).

• Flexible compensation: childcare vouchers.

• Flexible compensation: medical and dental insurance.

• Flexible working hours.

• Option for on-site, remote, or hybrid work depending on the situation.

• Cutting-edge technologies and technological updates.

• Opportunity to work in locations around the world.