If you include a keyboard, you're not going to do much better than a macbook air. A 13" iPad pro with keyboard is actually .3 lbs heavier at 3 lbs than a 13" MB

If you include a keyboard, you're not going to do much better than a macbook air. A 13" iPad pro with keyboard is actually .3 lbs heavier at 3 lbs than a 13" MBA at 2.7 lbs. The other issue with an ipad and coding is weight distribution. Tablets are too top heavy to work well in a clamshell setup if that's how you're going to use it.