It was a phone interview and they tested both technical and HR related stuff. They kindly introduced themselves and started with the generic question "tell us about yourself". After that they went over my resume and asked how much experience I have and what I specifically did with those techniques. Additionally, they asked questions how I work independently in the past. Overall, it was a pleasant phone interview and they told me that they would let me know if they decide to invite me for an on-site interview.