This seems more spam than anything else. What's new about their approach? Why is this relevant? I don't want to be mean but I don't understand why this is in Hacker News
They are the official search for HN itself. That should have given you the hint. They are a YC company, so surely these posts rank up, perhaps because the alum group do some voting for peers. Which I feel is a good side-effect of being in YC.