I applied through a recruiter. The process took 1 day. I interviewed at G-Research (London, England)
Interview
There was a technical test ( ~ 40m) and 2 face to face interview with 2 Senior SysAdmin. Unfortunately I cannot say anything about the technical test. The face to face interviews were about Linux Kernel , Bash scripting and multicast.
Interview questions [1]
Question 1
It was not "unexpected" but the 2nd face to face interview focused too much on multicast.