How readily does your code measure up?
The traditional measure of programmer productivity was how many lines of code did they produce, modified slightly to become how many error-free lines of code did they product. That of course had little to do with how efficiently the code ran, how frequently it broke down or what resources it took to fix it. We far beyond the "how many lines" metric but wise and balanced metrics remain hard to define and implement. Ease of update, ease of integration with production systems would be good ones.