Chinese cities are increasingly using digital technologies to address urban problems and govern society. However, little is known about how this digital turn has been implemented. This study explores the introduction of digital governance in Shenzhen, one of China’s most praised smart cities. We show that, at the local level, the successful implementation of digital systems faces numerous hurdles in long-standing data management and bureaucratic practices that are at least as challenging as the technical problems. Furthermore, the study finds that the digital systems in Shenzhen entail a creeping centralisation of data that potentially turns lower administrative government units into mere users of the city-level smart platforms rather than being in control of their own data resources. Smart city development and big data ambitions thereby imply shifting stakeholder relations at the local level and also pull non-governmental stakeholders, such as IT companies and research institutions, closer to new data flows and smart governance systems. The findings add to the discussion of big data–driven smart systems and their implications for governance processes in an authoritarian context.