Mainframe Modernization Engineer - COBOL/DB2 Expert

MasterCard; København; On-site; DKK 900,000 - 1,200,000; Full time

Job summary

Mastercard is hiring a Senior Software Engineer for Mainframe Development in Copenhagen. You will design, develop, and maintain COBOL/JCL/DB2-based applications on IBM z/OS, collaborating with global teams to modernize services and enable APIs while ensuring security standards are met.

The role requires 5+ years in mainframe development, strong z/OS knowledge, and experience with integration layers; you’ll participate in on-call duties and contribute to modernization efforts across platforms.

Qualifications

• 5+ years of experience in mainframe development (IBM z/OS, COBOL, JCL, DB2, SQL).
• Strong understanding of z/OS architecture and batch processing.
• Experience with file transfer gateways, and integration layers.
• Familiarity with Agile methodologies.
• Ability to work in a global team and communicate effectively across time zones.
• A passion for modernization and continuous improvement.

Responsibilities

• Design, develop, and maintain COBOL, JCL, and DB2-based applications on IBM z/OS.
• Collaborate with cross-functional teams to integrate mainframe services with distributed systems.
• Lead modernization efforts including migration to event-driven architectures and API enablement.
• Ensure compliance with Mastercard’s Mainframe Security Technical Standard.
• Participate in daily change request syncs and operational reviews.
• Contribute to the Software Engineering Guild’s leveling and performance standards.
• Participate in on-call duties outside working hours.

Skills

Mainframe development

Agile methodologies

Cross-time zone collaboration

System modernization

Tools

COBOL

JCL

DB2

SQL

z/OS

Job description

Mastercard is hiring a Senior Software Engineer for Mainframe Development in Copenhagen. You will design, develop, and maintain COBOL/JCL/DB2-based applications on IBM z/OS, collaborating with global teams to modernize services and enable APIs while ensuring security standards are met.

The role requires 5+ years in mainframe development, strong z/OS knowledge, and experience with integration layers; you’ll participate in on-call duties and contribute to modernization efforts across platforms.