Release candidate for an upcoming 4.0 stable version incorporating Claude Fable 5 feedback. While potentially relevant for tracking dependency updates, the article lacks technical specifics about what features or improvements were implemented.

SkyPilot now integrates with Hugging Face Hub via hf:// mount scheme, enabling seamless model/dataset access across multi-cloud GPU clusters without data egress costs. The integration uses hf-mount FUSE backend with lazy loading and intelligent caching, allowing training to start immediately while data streams in, and supports portable authentication via HF_TOKEN across AWS, GCP, Azure, and other platforms.