- Fortran and Cobol This is definitely the right general strategy: You want to ensure that compilers, libraries and a community are all available in 50 years.

- Fortran and Cobol This is definitely the right general strategy: You want to ensure that compilers, libraries and a community are all available in 50 years. This depends, in turn, on having a huge community of users with high-value legacy systems that can't be feasibly rewritten. So basically, you want to choose a boring, widely-adopted "enterprise" language, one used to implement a large number of critical back-office applications in Fortune 500 companies. You also want to choose a language which has a long history of backwards compatibility. In the 80s, Cobol would have been an excellent choice. Today, I'd probably go with Java for this role. Sure, there's a lot of boilerplate (or whatever your personal complaint might be). But in 2064, there will absolutely be a huge quantity of ugly legacy code written in Java, and it will still be running critical systems somewhere. At a minimum, there will be a small market of specialists who can maintain it, and Oracle (or one of their successors) will be happy to sell you a JVM and enterprise consulting services at a hideous markup.