Whatever you're experienced with. I know it's nice to write a backend in js and easy to learn Python, but if all you ever did is writing C#, then there's nothin

Whatever you're experienced with. I know it's nice to write a backend in js and easy to learn Python, but if all you ever did is writing C#, then there's nothing wrong with using it. You only know jQuery? Don't worry, you're probably being paid for the result and not for using React. (This is obviously not true if you want to learn new technologies)