Could you both expand on what you mean? I've built some useful stuff with langchain v1 but gave up on porting it to v2, looked like too much work.

Indeed, it has become the LLM equivalent of IBM, as in -- "No one ever got fired for choosing LangChain". A certain well-known ML person even runs a course on LangChain, as if it's a "fundamental" thing to know about LLMs. I was also surprised/disappointed to see that the otherwise excellent "Hands-on Large Language Models" book from O'Reilly has extensive examples using this library.

In Apr 2023 we (CMU/UW-Madison researchers) looked into this lib to build a simple RAG workflow that was slightly different from the canned "chains" like RetrievalQAConversation or others, and ended up wasting time hunting docs and notebooks all over the place and going up and down class hierarchies to find out what exactly was going on. We decided it shouldn't have to be this hard, and started building Langroid as an agent-oriented LLM programming framework.

In Langroid you set up a ChatAgent class which encapsulates an LLM-interface plus any state you'd like. There's a Task class that wraps an Agent and allows inter-agent communication and tool-handling. We have devs who've found our framework easy to understand and extend for their purposes, and some companies are using it in production (some have endorsed us publicly). A quick tour gives a flavor of Langroid: https://langroid.github.io/langroid/tutorials/langroid-tour/

It's unreasonable to expect that everyone is on top of every latest LLM advancement.