Mainframe Migration Engineer (COBOL/Java/Assembly) - Full Remote Portugal (Occasional Porto visits)

ABOUT THE OPPORTUNITY

Join a high-impact Mainframe Modernization project for a major enterprise client in Germany, delivered through an established international technology group with deep roots in complex systems engineering. This is a critical, fast-moving initiative.

Fully remote from Portugal, with occasional on-site visits to Porto (approximately once a month). 

PROJECT & CONTEXT

You'll be working on the migration of large-scale legacy Mainframe systems for a leading German enterprise — a technically demanding initiative that combines deep knowledge of existing architectures with the ability to modernize and rewrite in contemporary environments. The work involves analyzing and refactoring existing COBOL and Assembly codebases, supporting the transition to Java-based modern architectures, and operating across hybrid environments where legacy and modern systems coexist during the migration window.

This is not a maintenance role — it's active migration engineering with real complexity, tight timelines, and direct collaboration with international teams across Portugal and Germany. The kind of project where your experience with legacy systems is finally treated as the rare and valuable asset it is.

WHAT WE'RE LOOKING FOR (Required)

• Mid to Senior level — 5+ years of experience in software engineering with direct involvement in Mainframe environments
• Strong hands-on experience with at least two of the following: COBOL, Java, Assembly — depth in all three is a significant differentiator
• Proven experience in Mainframe migration or modernization projects — you understand the complexity of migrating business-critical legacy systems, not just reading the code
• Ability to analyze, document, and modernize existing legacy codebases — including understanding undocumented or poorly documented systems
• Comfortable operating in hybrid environments where Mainframe and modern stacks coexist
• Strong problem-solving skills in complex, low-tolerance-for-error contexts
• Able to onboard fast and contribute immediately — this project requires minimal ramp-up time
• English B2+ — working language for collaboration with international teams and German client stakeholders
• Willingness to travel to Porto approximately once a month when project needs require it

NICE TO HAVE (Preferred)

• Experience with German enterprise or banking/insurance/telco environments — common Mainframe domains where this client likely operates
• German language skills — even conversational level is a meaningful plus for client-side communication
• Familiarity with z/OS, JCL, VSAM, DB2, or CICS — core Mainframe ecosystem components frequently involved in migrations
• Experience with migration tooling or automated code conversion frameworks
• Background in code analysis and reverse engineering of undocumented legacy systems
• Prior exposure to microservices or cloud-native architectures as migration targets
• Experience working with distributed international teams across different time zones and cultures