Transformers

Transformers is Hugging Face's model-definition framework for state-of-the-art machine learning in text, vision, audio, and multimodal models for both inference and training. Supports 300+ model architectures with 3 new architectures added weekly. Over 1M+ model checkpoints on Hugging Face Hub. Transformers v5 (2025) narrows to PyTorch as primary backend for deeper optimization, introduces 'transformers serve' for OpenAI-compatible API deployment, and enhances inference with streamlined APIs, continuous batching, and paged attention. Over 1.2 billion total installs with 3 million daily installations.