I do all my development work (which involves a lot of heavy Scala stuff) on a 2012 MacBook Air, which is a wee bit slower than this one. The CPU really is not a problem.
There's no SSD or 'Fusion Drive' in this one, which will make it bog down a lot. It's a shame that Apple won't go for a $999 model with a 64GB SSD or something. Should be enough for classrooms and anyone who wants a basic computer.