This chapter introduces a metabolic perspective on infrastructures, enabling us to explore their roles in the extraction, circulation, and transformation of materials within contemporary societies. Positioned between what I distinguish as homeostatic and political ecology approaches, I propose a third avenue through the concept of 'metabolic pathways.' This concept facilitates an understanding of the socio-political implications associated with specific materials. To adopt this approach, one must broaden the consideration of infrastructures, encompassing not only socio-technical means but also the practices and networks of actors that collectively contribute to the formation of various forms of infrastructuring for metabolic pathways.Analyzing these strategies through the case of plastic waste in Cairo, employing a Deleuzian perspective, enables us to decipher the legitimization frameworks and power dynamics inherent in different strategies of infrastructuring for metabolic pathways. These strategies play a crucial role in shaping a specific socio-material order.