langchain - 💡(How to fix) Fix Add langchain-nebius as a partner package under libs/partners/ [1 comments, 2 participants]

Submission checklist

• This is a feature request, not a bug report or usage question.
• I added a clear and descriptive title that summarizes the feature request.
• I used the GitHub search to find a similar feature request and didn't find it.
• I checked the LangChain documentation and API reference to see if this feature already exists.
• This is not related to the langchain-community package.

Package

langchain (specifically: a new libs/partners/nebius/ directory)

Feature Description

Add langchain-nebius as a first-party partner integration under libs/partners/, matching the pattern recently used for openrouter (#35211) and perplexity (#30618).

Use Case

Nebius runs Token Factory (formerly Nebius AI Studio), a hosted inference platform for 60+ open-weight models including Llama, DeepSeek, Qwen, Mistral, and Kimi families. It's increasingly used as a cost-competitive alternative to other inference providers in the same tier (Fireworks, Groq, Together) for LangChain and LangGraph workloads.

A standalone langchain-nebius package already exists at https://github.com/nebius/langchain-nebius (PyPI: https://pypi.org/project/langchain-nebius/, currently v0.1.3). It exposes:

• ChatNebius — chat model (extends BaseChatOpenAI; supports tool calling, structured output, JSON mode, streaming)
• NebiusEmbeddings
• NebiusRetriever
• NebiusRetrievalTool and nebius_search

Nebius is also already listed in the LangChain provider docs at https://docs.langchain.com/oss/python/integrations/providers/nebius. The remaining gap is being colocated in the langchain monorepo so the package benefits from:

• The shared CI / lint / standard-tests infrastructure that other partner packages use
• langchain-profiles-managed model capability profiles (see libs/partners/fireworks/langchain_fireworks/data/_profiles.py)
• The release / model-profile-refresh automation
• Higher discoverability for users browsing libs/partners/

Proposed Solution

1. Onboarding conversation between LangChain maintainers and the langchain-nebius maintainer (@aktsvigun) on whether to (a) transfer the package into the monorepo, (b) dual-publish, or (c) take a different approach.
2. If approved, a PR mirroring #35211 (OpenRouter) that ports the existing source under libs/partners/nebius/, adds pyproject.toml/Makefile/CI hooks matching other partners, and wires up the standard ChatModelUnitTests / ChatModelIntegrationTests suites.

Additional Context

• Maintainer of the existing standalone package: @aktsvigun (Nebius)
• I've recently sent a series of small PRs and an audit issue against the standalone package: https://github.com/nebius/langchain-nebius/issues/4
• Happy to coordinate the port / take ownership of the partner-package PR work once a maintainer signals direction, per the template's "do not begin work on a PR unless explicitly assigned" guidance.