GenossGPT is an open-source server and Python package that abstracts multiple LLM backends behind a single OpenAI-compatible API interface. It supports providers including GPT4ALL, Llama V2, HuggingFace, Anthropic, and Vertex AI. Developers can swap any LLM into their application with minimal code changes, as the library exposes both chat completion and embedding endpoints that mirror the OpenAI API schema. The project runs as a local server exposing REST API documentation at localhost:4321.