As soon as I submitted my application, they were super quick to respond. The entire process was very transparent. I loved how much they cared about letting me know where things are internally. 'No update is also an update' - they stuck with this mantra throughout.
Overall, it started with a Slack conversation (this was one of a kind and brilliant since they're remote). The second round was a deep dive into my past experiences. The third round was a detailed technical interview. The last round was just an informal conversation coupled with the culture fit round.
The best part about the entire interview process was that they gave me very specific feedback on a call even though things didn't work out. I've only heard of companies doing this but it was nice to actually experience it :)