This workshop will introduce you to the concepts of building Large Language Model powered applications in Java using Quarkus and the LangChain4j library. Together, we will develop an enterprise application that integrates generative AI and starting from the basics, we will add more complex features, showcasing the different aspects of working with LLMs. The workshop will be delivered by key engineers of the Quarkus and LangChain4j projects and you will have the opportunity to ask all your questions. By the end of this day, you should have a good understanding of prompt engineering, model parameters, AI security aspects and RAG.