alt Hacker NewsLangchain and other frameworks are too bloated, it's good for demo, but highly recommend to build your own pipeline in production, it's not really that complicated, and you can have much better control over implementation. Plus you don't need 99% packages that comes with Langchain, reduce security vulnerabilities.
I've written a series of RAG notebooks on how to implement RAG in python directly, with minimal packages. I know it's not in Rust or C++, but it can give you some ideas on how to do things directly.
trouble is that the Langchain community is large and jumps on the latest research papers that come out almost immediately, which is a big advantage of your a small team