After Professor Luis von Ahn (co-founder) passed my name to the CTO, I waited a week to hear back. I eventually wrote a follow-up email. Before even talking to me on the phone, the CTO screened me by sending a coding task to do. I submitted it two days later and simply received a "it was good knowing you, but sorry we can't offer you a position" a few hours later. Not sure how well they got to "know" me through a coding assignment, because I definitely didn't get to know them.