1. Recruiter reached out; she was friendly and helpful. Had a great conversation.
2. Take-home challenge - took about a week (~15h). I actually thought the challenge was pretty fun, relevant, and creative. Specs were detailed and the team was responsive when I had questions. I didn't receive any feedback about my code, but they let me know that I passed very quickly.
3. Call with the hiring manager - this is where things went downhill. The hiring manager was cold, dismissive, and even laughed at my questions about team dynamics and culture fit. Since the recruiter did not have a specific team/manager in mind for me when I started the process, I wonder if the manager I spoke with was interested in my background in the first place.
If Slack didn't pride itself on having an "empathetic" culture, I wouldn't bother writing a review - but my experience with Slack was one of the worst out of all the companies I interviewed with (a mix of big and mid-size). Perhaps it was just a bad fit with that hiring manager, but I would've preferred to find out that I'm not a good fit before spending ~15h of my own time on a take-home assignment.