There were a few stages I went through - the first being a skype call with HR to talk about my academic life, interests etc. After passing that stage, I was sent a problem and was asked to code the solution. Upon doing that and passing that stage, another set of two skype calls followed - a technical one with two software developers in which they ask about your technical expertise and ask you questions on how you would deal with certain scenarios. The second one was with two other employees (not necessarily developers) to talk about the company's culture, their views, my views etc. Upon passing that, I had an in person interview at their office in Barcelona, this comprised of a logic test, a presentation (prepared beforehand) and a pair programming exercise looking over the code you submitted. Sadly I didn't get an offer, they felt that I needed to show more confidence when coding (as seen from the pair programming interview). However the feedback i received was great, very details and the HR co-ordinator even arranged a skype call to go over what she had said in the feedback email. I thought this was nice considering most times you get a generic 'no' email in other companies. I would 100% recommend!