I could add a couple things from my own experiences. Storing prompts in a database seemed like a good idea, but in practice it ended up being a disater. Storing the prompt in a python/typescript file, up front at the top, works well. Using OpenAI playground with it's ability to export a prompt works well, or even better, something in gradio running in vscode with debugging mode, works even better. Few shots with refinements works really well. LangChain did not work well for any of my cases, I might go as boldly as saying that using langchain is bad practice.