I think this is another crucial part. Right now, writing prompts is kinda like writing hand-crafted assembly back in the day where that was routine because there was simply no other way to get good results out of hardware in many cases - but also because the tasks that are actually doable do not require much code, so it's perfectly feasible to write it in assembly by hand.

LangChain is kinda like taking that state of hardware and bolting on a modern C++ compiler with templates and STL on it.