Do you have any information on how exactly Attlasian works (links to some presentations/posts would be great)? From what I know they are not even close to Github/Valve kind of flow. But I might be wrong.

Found this from 2011: http://www.managementexchange.com/story/its-culture-stupid-h...

and of course their official pages on it: https://www.atlassian.com/company/about/values

Maybe that explains why there are 5 year old critical bugs in their products...

Maybe you can elaborate why you are mentioning them here?