[D] What does a production level RAG Application really consist of

I've done my research on RAG, implemented a few naive RAG tutorials and I'm aware of the advanced RAG techniques I now want to implement. But I don't really know what that proper application workflow looks like. Like what makes the difference between implementing those 7 lines of code in a naive RAG tutorial and then adding stuff like hybrid search or reranking, and actually building a production level RAG application? What does that 'workflow' look like?

advanced application code difference machinelearning production rag research tutorials workflow