Langchain Orchestration

If you're building with LangChain beyond toy examples, this covers the orchestration patterns you'll actually need. It walks through LCEL composition, sequential and parallel chains, routing logic, and the Runnable interface that ties everything together. The examples show real patterns like map-reduce for parallel processing and conditional branching for dynamic workflows. What's helpful here is seeing how chains compose using the pipe operator and how to handle streaming, async, and batch operations consistently. It doesn't cover agents or RAG deeply despite mentioning them in tags, but the chain orchestration fundamentals are solid. Good reference when you're moving from proof of concept to something that needs proper flow control.