Alibaba

They call you ahead of time to schedule an interview. It's a phone interview, but there's a website where you have to complete five programming problems. I didn't do them all.

Phone interview after referral. No appointment was scheduled before the call, and the interview date could not be changed. This was very disadvantageous, as I had limited preparation time. The interview lasted 15 minutes.

The employer asked about basic data structures and algorithms, and presented a problem for me to solve. It was not very difficult, but it should take a while to think. You may ask for hints if you wish.