Annotorious is an open source JavaScript library that adds image annotation capabilities to web applications with minimal setup.

It integrates seamlessly with OpenSeadragon and supports high-resolution, zoomable images, including IIIF content. Annotorious is fully compatible with the W3C Web Annotation Data Model, and provides a flexible JavaScript and TypeScript API for building custom annotation tools and workflows.

I created Annotorious in 2014 and have been actively maintaining it since. The library is widely used in digital humanities and cultural heritage projects and forms a core component in several of my other projects, including Recogito Studio, IMMARKUS and liiive.