HR Interview
The interview was over the phone within about 15 minutes. The interview is in Bulgarian (since this is my place of residence), but several questions are asked in English. Finally, a range of desired remuneration is inquired.
Technical Interview
After the HR interview they send a test via email which includes basic technical questions. If you have done well in the test, a technical interview follows. For me it took about an 1 hour, including the standard technical questions, mainly theoretical.