"Authenticated Transfer Protocol" A [[Software]] protocol for message passing. Competes with ActivityPub. Is largely decentralized and has a few implementations and use cases. Primarily developed for the [[BlueSky]] social network. # Resources - https://sdk.blue/ - [Introduction to ATProto](https://mackuba.eu/2025/08/20/introduction-to-atproto/) - [A Social Filesystem](https://overreacted.io/a-social-filesystem/) - [getair.space](https://getair.space/) - Uses the new experimental Spaces API to make basically anything on top of PDS - JS/TS API