Interested in building a fediverse app but daunted by the complexity of ActivityPub? This post introduces Fedify, a TypeScript framework designed to simplify ActivityPub development. Implementing ActivityPub from scratch involves navigating complex standards like ActivityStreams and JSON-LD, which can lead to verbose and error-prone code. Fedify tackles these challenges with its type-safe Activity Vocabulary API, automatically handling JSON-LD nuances and providing a consistent interface. It also simplifies actor discovery using the WebFinger protocol, manages content negotiation, and streamlines core ActivityPub mechanics like handling requests and collections. Furthermore, Fedify ensures reliable activity delivery with its MessageQueue abstraction and prioritizes security by automatically handling HTTP Signatures and providing SSRF protection. With tools like the `fedify` CLI, Fedify enhances the developer experience, allowing you to focus on building unique features rather than wrestling with low-level protocol details. This post highlights how Fedify offers a secure and efficient foundation for building fediverse applications, enabling developers to bring their visions to life more quickly and reliably.