Lots of waiting. I initially sent in my resume for the position and it took weeks to get the first response. Expect every step of an interview to take at least 1 week. They want you to do a phone interview, you'll wait a week to hear back, then an online code test, then wait a week to hear back, then an in-person interview. This is where they fell off the face of the Earth. Technically the process isn't finished (and I'm not sure I'll ever actually hear back even after multiple follow-ups). For a HR company, it doesn't seem that they can even manage their internal HR processes that well.