First stage was a simple 30-45 minute interview about yourself. Including an overview of any projects you've done and how you went about them, but mainly about your own personality and work ethic. They also asked what programming languages you are most comfortable with and why, which languages you prefer over others, etc.
Then the second stage (if invited to it) is an in person interview, which for some reason I didnt clock it would be more like an assessment centre. More interview questions and a system design challenge (UML diagram in my case, but they dont expect you to know about it really, just do it however you prefer). Thats about it, really nice people and a really straightforward process, not too technical.