i am 40 and am worried about retirement. what sort of retirement planning did you do? how much do you think is a good plan. i love startups, i see similar aspiration to continue to work for startups till 60. i am not interested in creating any sort of generational weath or such as i am already doing what i would like to do, large sum of money won't change anything. but i am asking so i can be a bit peaceful to know some advise from my senior.