This document discusses the emergence of library chatbots in Germany and the experiences of libraries that implemented them. It describes the process of creating a chatbot named Stella at the Hamburg State and University Library. Stella was able to answer around 250 questions per day on library-related topics, with accuracy improving over time. Evaluations found that chatbots can effectively provide 24/7 basic reference, but more complex questions require a human librarian. Chatbots may be most useful for marketing other library services.