Interview with PM, then take home coding challenge, then review of coding challenge with dev team, the interview with upper management (only 2/4 showed), then an onsite showcase of the company. The whole process took about 2 months.

The process I went through took about a month only because I was employed at the time. It consisted of a phone screen, an in person meeting, a code challenge, a dev team meeting and a bunch of other meetings with senior management and other team members.