Job interviews for computer programmers are full of bias

(written by lawrence krubner, however indented passages are often quotes). You can contact lawrence at:


Confidence bias selects for candidates who are good at interviewing.

There are people who have the social skills to actively listen to someone else’s technical points, to guide a discussion with questions of their own, or to spot opportunities to redirect a tough question back to familiar territory. Those people build impressive resumes. They effortlessly pass “culture fit” tests. And a lot of them can’t code.

Confidence bias excludes candidates who don’t interview well.

For every genuinely competent and effective developer who can ace a tough dev interview, there are many more genuinely competent and effective developers who can’t. While we’re selecting for the ability to control a conversation, we’re missing ability to fix broken 2-phase commits.

You can look at this like a moral problem. Me, I just see money hats. I am on a mission to eradicate the software developer job interview. I hope and expect to be pursuing that mission twenty years from now.

Meanwhile, let’s contain the damage. There are things you can do to make your hiring processes better. I’ve deployed these tactics. I’ve seen them work. They should be industry standard. They aren’t yet. Adopt them and profit.

More often than not, when the interviewer’s gut-check “yes/no” departed from the data, we’d find that the untrustworthy source was the interviewer. Despite training them not to, they routinely factored “confidence” into their result. Biases like that are pernicious!

You should also consider eliminating phone screens. We didn’t, but we did the next best thing: I simply began disregarding all but the most notably bad phone screen results. You could get selected out of our process by being an asshole on a phone screen, but there was little else you could do to fail.

Phone screens carry almost every liability of interviews but further hamstring the candidate and the interviewer by occurring at a distance, being hastily scheduled, and, for the hiring team, having implicitly lower stakes than the in-person interview. After improving the rest of our selection process, I asked myself, when would I be comfortable denying a candidate the opportunity to further demonstrate their ability based on the outcome of a phone call? The answer was “virtually never”.