Congrats Marc! We've been using Langfuse for about 6-months for our LLMOps tooling. While its SDKs are limited to python and typescript, their openapi specification is pretty easy to implement in any language.

The team behind it is amazing, and their product being OSS is one of the reasons we chose it. But it just keeps getting better.

We're incidentally only using part of the product because we've implemented most of these new features, prompt caching, execution etc in our app. But with the API you can decide what parts are core to your business logic and outsource the parts you don't want to deal with to Langfuse.

I appreciate that its not an opionated product.