A few things to say up front: I don’t know Zatko myself, and am only passingly familiar with his work. Some people I know deeply respect and trust him, and many of them tweeted tributes to him today. Other people I know who worked with him had a lesser opinion of his work; these people spent today sending me messages that began with something along the lines of “Here is a story about Mudge that you can’t use.” (A few, though, did tweet their criticisms publicly.)