Comment by ml-

For me it has been cross pollination. Do things that help with all other aspects of being human, and it will pay off in the long run. What that means is highly subjective and personal.

After being in the field for a little while you come to realize that languages are just dialects on the same core, new tech and frameworks are mostly just different wrapping, and that the core tenets and fundamentals that you know will always be there in some form.

What will help you with longevity are things that are not traditionally looked at as SWE skills. Things like empathy for users and other developers, communication skills, being able to iteratively create user value, understanding costs of delays and that perfect is rarely what we want, etc, etc, etc.. Solving logic issues with algorithms is such a minute part of what we do, and the part most likely to be automated at some point.