Do you have any example what technology gave you a clean upgrade path from 2005 until now, without the need to do major changes? With .NET you can still, use m

Do you have any example what technology gave you a clean upgrade path from 2005 until now, without the need to do major changes? With .NET you can still, use most of your code from 2001, just the UI frameworks (and WCF) are not supported anymore on .NET 5+. They are supported at least until 2031 on .NET 4.8. So you can easily move your business logic to a newer version and leave the UI on an older version. But seriously, who is still happy with a web application built in 2005?