Call with the hiring manager, CTO and director. There was an exercise to describe in writing a challenging experience you'd encountered. All standard product stuff and nothing too technical. Process took about 2 weeks in total. They then pulled the job last minute and sent a email without really apologising for wasting my time

Initial screening call, product sense interview, written task about 'challenges' in previous roles, interviews with chief commercial and head of engineering. I was invited to a final stage to meet the CEO only to have that reneged 20 minutes later because 'they'd decided not to hire anymore'