1/x As many of us know, cognitive bias is a huge problem when hiring under-represented in groups in tech, this bias is subconscious and has been proven to affect all levels of intelligence equally.
2/x You might not consciously pass over one of these people but your brains pattern recognition will still make it harder for them because, for many of us, it has been trained to think that a developer is a white male and the woman/tg/person of colour/etc does not fit the pattern
3/x An interesting story about this is when an orchestra was trying to hire more diverse members. Even with that mission in mind, they kept hiring white men because they were "the best choice", even though there was no evidence for that.
4/x So, they started doing blind interviews, where people were behind a screen and played their instrument with the interviewer not being able too see the artist while listening to them play.
5/x With this change, the amount of non-white men being hired shot up dramatically but women, of any colour, still lagged behind. This puzzled them for a while, until they refined the test a bit more. They asked applicants to take of their shoes before entering.
6/x The reasoning behind this, was that women dressed up for an interview were likely to wear heels, and as this was a musical test, the interviewers' acute hearing picked up on this and the cognitive bias kicked in, making the amount of women hired lower.
7/x Once they started doing the shoe-less blind tests, the amount of women hired shot up to equal levels as the other groups and they finally solved their diversity problem. So you can see, even when consciously willing to hire for diversity, bias can get in the way.
8/x This is one of the main reasons why hiring quotas exist, because often, even the best willed of us can have a subconscious voice whispering that the white man "is just the best candidate" even if that's objectively isn't the case. Quotas can force us to ignore that voice.
9/x Of course the best way is to try and get rid of our biases, but this is a lot harder than it sounds, especially as your biased is reinforced every time you see a conference or office filled with white men.
10/x The only way of overcoming this bias is by being exposed to enough talented people that don't follow your brains expected pattern. You can start that right away, there are enough great people from under-represented groups right here on twitter, start following them!
11/x Start making your timeline more diverse and after a while, your brain's pattern matching might let go of its bias and you will not make people who are not white men work orders of magnitude more to prove themselves, even if you don't mean to.
12/12 Do this especially if you interview people for your company or if you are in a promotional review board. And if you don't see the use of diversity in tech, you should especially follow them, to see what you're missing out on.
Addendum: A big part of this thread was inspired by this great talk by @annaraven