No HR interview.
In the technical interview get ready to be grilled about everything you mention (so don't say you know something if you really do not). I understood it as them being condescending at the time of the interview, but they are really just trying to figure out your limits. After the first interview, you get a task sent to you that you have to finish in a week. The task is relatively small but you really need to give out the best solution so if you add attention to detail and try to optimize it as much as possible it amounts to one week of work. Once you send out a solution you have an additional interview where you discuss the task solution so be prepared to explain your work. After that interview you get an email with the decision.