"In their book, Digital Technologies, Smart Cities and the Environment: In the Ruins of Broken Promises, Adi Kunstman and Liu Xin unsettle the very ground of the digital as exclusively virtual, building connections between environmental justice and social justice in how we understand smart cities and technology. Through the frame of broken promises and a deft examination of failures and ruins, they shift our understanding of smart cities from sustainability or surveillance to accountability, and question ways the digital is constructed through various social, political and economic actors as inevitable. Thoroughly researched and thoughtfully theorised, the book is an urgent and clarion call to reflect on what remains in a time of ecological crisis and techno-solutionist paradigms."Xiaowei Wang, University of California, Los Angeles and the author of Blockchain Chicken Farm: And Other Stories of Tech in China's Countryside