All (?) the "open" (to various degrees of openness) LLMs are on HuggingFace and have code to support their unique options. For example here is Llama[1] and here is Opt[2].

All the code I've seen for training them uses Hugging Face. When EleutherAI releases their open foundation LLM then everyone will want to fine tune it and do RLHF on it and they'll all use HuggingFace code to do it.

I think they are in the best position of any company including OpenAI.

[1] https://huggingface.co/docs/transformers/main/model_doc/llam...

[2] https://huggingface.co/docs/transformers/main/model_doc/opt