The process took about a month long from start to finish; there were about 4 steps after contacting Gusto regarding my interest. First, I had an intro call with a recruiter to learn more about the company, second was a video call with the hiring manager, third was onsite #1 to present my design portfolio to a panel of 6-7 people on the team I would be joining, and lastly was onsite #2 to have 1:1 interviews with various cross functional team members. They also have you interview with someone random / outside of your department so they can determine if you will be a good culture fit.
The process was very involved and a tad overwhelming, but everyone who interviewed me was extremely kind, friendly and made the experience very enjoyable!