I haven't had it catch something before the compiler in a while. I still use typespecs for their documentation benefit, though I've been using `defguard` w/ `is_struct/2` and complex guards a lot more in recent years.

I still use the Typespec syntax for its documentation benefits, and for catching "dumb" bugs, but as the Elixir compiler has improved I have found Dialyzer to be less relevant as the compiler usually catches things before Dialyzer would as it's not built into the compiler and isn't able to be.

There's a langchain implementation that's fairly mature and definitely in production use (I saw the authors handle above actually :D ). Langgraph-style libraries exist (there's one called Magus that I've used) but I think that's where there could be some more efforts. Although it's important to note that building something comparable to langgraph isn't too hard in Elixir with its process model, and most Elixir devs could probably do it, but unfortunately that's not obvious to your average person searching "langgraph implementation in Elixir". There's no langsmith integration but the telemetry implementation in Erlang and Elixir is really nice so once some patterns around running chains and graphs emerge publicly (there's a few companies that I'd bet have private repos implementing their own equivalents of langgraph) I imagine integrating to langsmith would go pretty quick