There's more to life than writing code or being a technical wizard. Developers should know how to do way more than that or else they won't remain good developers for long. You can strive to have a great career and still be a whole person.
Here are three completely unrelated things that every developer should be able to do:
You have to have some other interests in life. Coding is cool, but it's not really something you should be doing 24/7. That's just unhealthy. It's easy to get absorbed into learning as much about web development as you can and it's ok to fight that urge occasionally.
Remember your other hobbies like whittling wood or playing the ukulele. You're not a code writing robot so enjoy the other parts of your brain. If there's a new restaurant you've been thinking about trying, go check it out. Just step away from the editor for a while and relax.
There's no need to work out like an athlete, but you do need to get up and move. When you're working on code all day it's easy to sit at a screen and not move for hours. It's one of the absolute worst things you can do for your health and your coding abilities.
Even if you just go for a walk around the block or pace around for a few minutes, get up and move. Do it now if you've been sitting down for over an hour. Your health is the most valuable thing you have so don't forget about it.
People reading is an art. You're used to looking at the smallest details in your code so why not observe the details of the people you work with? Learn what makes the people around you tick and it'll help improve your ability to get things done both at work and at home.
This is a skill that will help you ten times more than any technical skill you can learn. If you ever decide to freelance or you need to get a new job, knowing how to read people will help you tremendously. It takes some time to get good at reading people but once you know how to do it, you'll be the most powerful developer out here.
You can do so many other things that aren't on this list. The main thing is for you to do those other things. Improving your programming skills is great, but so is improving your tap dancing skills. Live your life outside of the editors. Please!
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