The alternative is to just simply continue maintaining the working COBOL system. If a programmer can't find their way around in a different programming language

The alternative is to just simply continue maintaining the working COBOL system. If a programmer can't find their way around in a different programming language then they really shouldn't call themselves programmers. The original COBOL system most likely has a much simpler structure than any modern rewrite would have (if the modern rewrite follows modern 'best practices' which tends to obscure the actual work under layers and layers of abstraction). Instead migrate that old COBOL system to new hardware (in emulators if needed), put a modern web-based UI on top of it, keep adding to the documentation and maintenance procedures, add tests written in modern languages, add a modern build infrastructure, etc etc... but think twice before replacing the part that does the actual work (there is actually a good chance the 'bug' is just in an UI layer that was added later, it may not know that a zero-birthdate should be displayed as 'unknown birthdate'). > I.e. let it burn and hope something rises from the ashes. That's exactly what a rewrite in another language would be.