I've posted about my personal experiences and how I've personally discouraged all sorts of contributors by ignorance in the past here on HN. For example, I re-submitted recently this blog post on a back and forth that I had with antirez: http://jculpon.github.io/fighting-sexism.html

We were able to resolve that via some twitter messages and some time to let both of us calm down, but at the time I was ready to stop using redis, much less helping folks via bug reports and patches.