It really depends on how you manage your career, I for one plan to work to 70s by coding, just love doing that. My theorem is that, many professors are still do

It really depends on how you manage your career, I for one plan to work to 70s by coding, just love doing that. My theorem is that, many professors are still doing researching and teaching PhD students in their 60s/70s, software developers is no different, unless you give up learning yourself. Anyway just want to say, if you really like being a programmer, no need for Plan B at 40, just keep learning and coding like a 'professor'