Cirrus is a digital annotation and writing platform developed at the University of Queensland to support student learning. It offers four types of annotation for texts, images, audio, and video, as well as options for digital writing in multi-tabbed webpages or parallax webpages. Cirrus has been used by over 4,000 UQ students since 2016 across various course sizes. It allows students to directly engage with course materials and analyze a variety of content, while also giving instructors insights into student work. All annotation and writing tasks can be set up individually or collaboratively to support group work.