Abstract
<title>Abstract</title> <p> Urban design theory has been largely shaped in temperate Euro‑American contexts, even as some of the most intensive urban transformations now unfold in the tropical Global South. This article examines Nusantara (IKN), Indonesia’s new capital, as a site where inherited urban design vocabularies begin to fray. Framed through the interlocking imaginaries of forest city, sponge city and smart city, IKN is approached as a material and epistemic assemblage in which ecological restoration, hydrological adaptation and digital infrastructure are brought into uneasy relation. Through qualitative interpretive analysis of legal, planning and policy documents, the article shows that this triad operates as a layered and often contradictory design doctrine rather than a seamless urban vision. From this tension it develops <italic>cyberphilic</italic> design as a mid‑range concept naming a design logic in which attachment to digital‑cyber systems is actively cultivated as a constitutive condition of urban life, and argues that theorising from the tropical Global South is an epistemic necessity for understanding digitally mediated urbanism. </p>