GUN is an open source cybersecurity protocol for syncing decentralized graph data, enabling developers to build community-run and encrypted applications. It serves as a decentralized alternative to platforms like Firebase or Dropbox, offering real-time peer-to-peer state synchronization and offline-first capabilities. Designed for developers building collaborative, secure, and scalable applications, GUN is used by projects like the Internet Archive and supports a wide range of use cases, from video conferencing to social media platforms.