From Geoff Sharman, Winchester, Hampshire, UK
The idea that “we’re still using decades-old code” comes as no surprise to those who have worked for long-established computer firms. One example is IBM’s CICS software, first released in 1969. It still supports a majority of online banking, insurance, stock trading and credit card applications, as well as applications in other industries and government, with very high reliability and performance.
The best way to think about long-lived software is to view it as essential infrastructure, akin to the Roman roads and 19th-century railways that many of us still travel on. Although they must be continuously maintained and improved, these systems use recognisably similar technology and follow the same routes. Why should software be any different?
