The **manifesto** library provides JavaScript utilities for working with the IIIF Presentation API, offering both client‑side helpers for consuming IIIF manifests and server‑side tools for generating and validating them. It targets developers building digital‑heritage, museum, library, or cultural‑institution applications that need to integrate IIIF content, and includes documentation, tests, and a publishable npm package. (A 3‑D extension is being developed in a separate fork.)