This article is a thinly veiled ad for their own site. Clickbait title, starts off with an implication that to prepare for interviews you should be reading their site... oh, and then sure, they write an article, too. But everyone on HN should be clever enough to see through this as little more than cheap marketing.
The sad thing is that I'm currently job hunting, I'm interested enough to give a minute or two of my day to review some content of this type, I do use their website to review companies, but then... they have to go and cheapen the whole experience for both of us by coming on so hard.
Now, instead of being mildly intrigued by what they had to offer, I just feel dirty for looking and want to go take a shower.