Aleph Alpha interview questions

The interview process I had with this company felt quite unprofessional. At the beginning it seemed normal. I had an HR interview, and then they sent me a take-home assignment. I spent quite a bit of time on it and structured it really well, honestly going beyond what they asked for. After that, we had a session to go through the task. One of the engineering managers on the call seemed to really like it and the way I approached it. They asked some general and technical questions related to the task and even asked me to make a small change live during the call. The next step was another interview with a different hiring manager. After that session, they reached out and said the engineering manager thought I was a good fit, but not for that specific team. They asked if I’d be open to interviewing with another manager for a different team. I said yes. I had another interview, and after that they told me the same thing again, that I seemed like a good developer and a good fit, just not for that team. They mentioned they liked my profile and wanted to find the right place for me. Since I was interested in what they were doing, I agreed to go through another interview. After going through this final round, they eventually sent me an offer. I accepted it and even resigned from my current job. But after I signed the contract and was waiting for the CEO’s final signature, they emailed me saying they had decided to cancel the new hire and withdraw the offer due to some internal changes. There wasn’t any real explanation. Overall, the way they handled it felt very unprofessional, and the whole experience left a really bad impression.