First, they sent me 20+ questions for me to answer via email. Most of the questions were very technical, dealing with malware (decoding), scripting (had to write a few scripts), DNS, other things. It took me 6+ hours to answer all of them over the course of the weekend. It seemed like I did a good job on them, because I had two follow-up conversations over Skype after that. The conversations themselves were not super technical, more about previous experience, what's your strongest trait, etc.
The conversation came to a halt when I was asked about my salary expectations, which really shocked me. I live in one of the most expensive areas in the US and make a decent salary, so I suggested a range that was slightly more than what I was currently making, and that really was a conversation ender. I had read on Glassdoor (and one of the interviewers had confirmed) that Sucuri pays well, so I thought I'd be fine. Yet, there was no counter-offer, no negotiation, nothing. The interviewer's attitude seemed to change, and I was just taken aback at how it was handled. It just seemed very unprofessional. All the replies were super short. He said he'd talk to his CTO about it (while being very negative) and didn't get back to me for a week. I finally emailed back to see how things were going and got a very simple "that's too much" email - no explanation, no courtesy. I tried to be reasonable and even tried to lower my expectations, but again, nothing.
I completely understand if a company isn't able to pay what someone is asking for, but there's a way to go about negotiating, or even ending a conversation gracefully. What I would suggest in this particular case is to let HR handled the 'salary' conversation, and not let the actual hiring manager do it, unless he's trained in that kind of thing. Another idea would be to discuss salary expectations *before* the conversation starts and candidates spend so much time working on the problems.
I did enjoy working on the technical questions, but it's a shame that I put in so much time and effort out of my personal time, to then be disappointed by the lack of professionalism when it came to salary negotiation, of all things.