Antumbra.xyz was a decentralised autonomous broadcasting organisation founded within the Architectural Association. Conceived as a space for alternative routes of knowledge and governance, it treated information as a material condition and explored broadcasting as a practice of convening, re-routing attention, and assembling publics.

The platform included an experimental interface that archived discussions, contributions, and associations, with its first network-scrape, Warmth, active from May to December 2022. Antumbra fostered a culture of experimentation and open coordination, where participation meant shaping the organisation itself.

Ultimately, the proposal was not continued by students at the Architectural Association, who chose instead to pursue printed matter as their medium of exchange. Antumbra remains as an archival trace of how broadcasting might act as both communication infrastructure and governance experiment.