> Put a tie on. Even better, wear a suit.

This is going to get a lot of mixed response, in part because it's so contextual. On the east coast, for instance, it's not uncommon to dress up for interviews (even for some dev positions, but not all).

However, in the Bay Area it would be completely unheard of for an engineer to show up to an interview wearing a suit. Honestly, it would look absurd.