Learn how to modernize legacy applications that have been in use for 10-30 years through this comprehensive conference talk from NDC Copenhagen 2025. Discover practical strategies for dealing with business-critical applications that represent single points of failure and are maintained only on an "as needed" basis. Explore the key decision-making factors that determine modernization approaches, including scalability requirements, safety and privacy concerns, and performance needs. Gain insights from an experienced application modernization architect who shares real-world project experiences and proven methodologies. Understand where to begin the modernization process and learn the essential steps needed to bring legacy systems into the modern age without the prohibitive costs of complete rewrites. Master the art of making informed choices about when to modernize versus when to rebuild, based on specific business requirements and constraints.