I applied on a Sunday evening and got an email on Monday from a Calendly recruiter wanting to schedule a phone screen. The recruiter was knowledgeable, friendly and upfront about the job and expectations. I then had a short phone screen with the Director of Engineering. He asked great questions and gave a lot of detail about the team and the role. I was then asked to complete a small project and an onsite interview was scheduled at the same time. I received an email with a detailed scheduled for the onsite interview, which included what sorts of things might be discussed or asked in each session. There were 5 sessions: one focused on system design, one for the project walkthrough and extension, pairing with another engineer on an actual Calendly bug fix, a culture session, and then a final interview with the hiring manager.
It's very clear that everyone involved in designing the interview process at Calendly put a lot of thought, effort and time into it. Things were very well organized and I was super impressed the whole way through!