Pros
The employment process is very smooth and supportive. The technical team interviewed me for technical skills, and the HR is very supportive and helpful. Especially I haven't been employed by CERN previously, so I have a lot of questions. The employment team is very helpful and answered all my questions patiently. Also I like the job and my work very much.
Cons
Maybe the primary communication method could be email instead of phone calls? I sometimes miss phone calls, but will check every email.