Don't waste your time. The process is taking very long and they don't know what they are looking for.
1. Introduction Call with recruiter
2. VP of Product
3. CEO
4. On-site with Product, Tech Leads, CEO debriefing a case study
Between each step it takes 2 weeks. Some of the people working there seem quite nice and experienced but some of them are also quite arrogant and delusional. I wonder if they actually know what they are looking for. I would not be sruprised if they don't fill this position at all in the end.