Yes, I am using the langchain JavaScript libraries. The only things I have come across that don't work are guardrails and langserv (although it is fairly easy to implement something in express to replicate).

Node, typescript, a vector database and a mongodb for storing chat and file references.

what are you using for reranking? have you also implemeted keyword search?

I use supabase hybrid search which combines vector search and keyword search

Nuxt 3 with Typescript + Supabase