Building a user-facing GenAI product within the fast-paced news environment of a public broadcaster is hard. This talk shares a collection of hard-earned architectural lessons from a real use case: from Denial-of-Wallet prevention, to why caching is key for controlling costs. We discuss concrete engineering solutions for preventing hallucinations or dealing with interconnected documents. Join this session to bypass the trial-and-error phase and discover what it really takes to run GenAI.