This article proposes a debate anchored in a dialogue between concepts of insurgent planning and humane urbanism and the idea of a subaltern urbanism through the lens of a critical reflection on the role of city-building professionals. The paper explores the idea of an insurgent urbanism as a collaborative praxis of city design and development that arises from the protagonism of marginalised communities and the accumulative knowledge of social movements, activists and scholars. It focuses on three different learning dimensions based on the experience of teaching/research actions developed at a self-organised squat in the metropolitan region of Rio de Janeiro, Brazil between 2018 and 2022. Dialoguing with ideas of social learning, it shows that these practices have created a relevant exchange of different types of knowledge and have contributed to the development of other solutions that challenge the hegemonic and neoliberal city production and can therefore be seen as alternatives for the development of more egalitarian and imaginative futures that expand beyond the context of squats in Brazil.