How can you determine objectively, over time, that you are getting any better at producing code? For example, I may sit here and feel that "I know <language> now, and I use <technique> now, so I must be better." But this does not account for my own bias, or the fact that I may be getting better at a slower rate than intended, or I may actually suck at <technique> and not realize it. What methods are available for one to objectively rate one's own abilities? What about to objectively compare them to their peer groups?