It was lengthy, but not out of norm of new tech companies that want to look modern. One requiter, one hiring manager, one assignment, and one owner. For me the strange part and the disrespectful part was that some point throughout the process they asked for my references! Which is usually asked when you are ready to provide an offer. I refused to offer it and said I would prefer for them to be contacted when you are ready to make an offer, and they responded back saying, they feel optimistic about me and this is normal in France, which actually I was told is not the norm in France. So finally, I had two more interviews with the manager which she said she feels good about it and very interested, so I could give them my references. But once I did, they never called them and didn't hear from them for like a month, even though I was told they will be contacted and I gave notice to my contacts no effort was made on their part and came back saying they decided to go with other candidates as didn't they feel like it was a good fit. I was quite upset that I had put my name on the line told my references and bothered them tone available for a call and they never did. If you have no intention to call references, it is quite unprofessional to ask for it.
Overall, I found the company strange, asking strange low level questions during assignment and the process very disrespectful of the candidate time. I don't recommend interviewing here.