Sernesto GmbH – with roots in 2016 – has repeatedly seen the same challenge in numerous projects with banks and insurance companies: 

Critical core systems have been running on COBOL and mainframe for decades, but experts are becoming scarce.

This real market demand led to the establishment of 2024 in Olching near Munich of the RetroCode GmbH – a company that is fully focused on the stabilization, further development, and modernization of COBOL and legacy systems .

In 2025, we started with an experienced team of senior software developers, whom we specifically trained in COBOL and mainframe technologies through our own training program. Since then, we have reliably supported banks, insurance companies, and industrial enterprises exactly where modern IT approaches meet decades-old, business-critical systems.

RetroCode bridges the gap between old and new – with deep know-how, many years of practical experience, and a clear focus on business-critical systems.

Our mission is to secure the stability and future of critical COBOL and mainframe systems – by reliably continuing to operate, further develop, and gradually modernize them as needed.

With our legacy know-how and modern software expertise, we give our clients the freedom to maintain their proven systems while also having the option to transition to modern IT architectures at any time.

Innovation with Sense

We love technology – but even more, we love solutions that work. Curiosity, pragmatism, and the courage to take new paths drive us.

We question the status quo and use modern methods and tools to create real value – without complexity for the sake of complexity.

Trust & Transparency 

Success arises where people interact openly. We clearly address opportunities, challenges, and risks and work with our clients as partners – honestly, reliably, and on equal footing.

Team Spirit & Collaboration

We work with passion, share knowledge, laugh together, and learn every day. Our team spirit does not end at our doors: We see ourselves as an extension of our clients' teams – together, solution-oriented, and always respectful.