There is no proper interview process. Simply they will call you for an interview. For me they called for PostgreSQL DBA I told them clearly that I don't have exp in MongoDB. 4 rounds.. On a whole they have taken 4.30 hrs of interview within a day.I  have been so tired.. Finally they rejected me by saying I don't know MongoDB and they r not ready to teach me  My question if they are looking for combo of PostgreSQL and Mongo y they called up for an interview and wastedy whole day..