It's been one of the greatest interview experience I've had thus far (And, I interviewed with two out of 4 Big Tech companies). It's a fairly quick process though.
Shortly after submitting the application, I received an email from a recruiter at Thumbtack. She helped me to schedule a phone interview with the hiring manager. The interview went well. Then, after a couple of days, I received a case study, which I had a week to complete. The case study basically related to Thumbtack business model.
I got an update of moving to onsite interview after 4-5 days or so. The recruiter promptly scheduled an onsite interview for me. There, I met with 5 different members of Thumbtack's team.
After the onsite, supposingly I need to wait for 1-2 weeks for the final result. However, at that time, I had two other offers that need to be answered in the next couple days. I informed the recruiter. She got back and asked if I could schedule one more onsite interview ( since I was one of the earliest candidates going to onsite round, they had few candidates to compare. They wanted to meet me one more time before making an offer), which btw I think, is fair.
Two days later, the hiring manager called me directly for the offer. It was a relatively competitive offer.
Overall, the process took me around 3 weeks ( from application to offer). Every member in the team was nice, cheerful, and very smart