There is no one size fits all measurement developer productivity. Let me explain. The summer of 2006 was when I got my first "real" dev job. You know, the kind where you had to sign a W-2, pay taxes, and everything. While I was building software as an indie dev, this was a bit of a change. This job sucked. If you were a minute late they'd dock your pay. If you took lunch, they'd look down at you. Their version of measuring developer productivity was how long you were at your desk. It was a ridiculous place to work. I quit a few months into it and never looked back.