This SIG calls for a global conversation around platform (in)justice. By focusing on the experiences of people residing in the Majority World (also known as Global South), we aim at creating a space for international and interdisciplinary exchange on socio-economically, politically, and culturally sensitive platform design and operation. The following topics motivate the SIG: concerns about equal access, structural discrimination, global inequities, and the desire to find solutions to those challenges. We invite the CSCW community to explore how attention to power relations, colonial residual, geopolitical tensions, and historical specificities can lead us to more sustainable and just platform designs. Through our SIG, we aspire to shape a research agenda for platform (in)justice that centers best practices and solutions to mediate some of the harms previously identified in the CSCW community. Going beyond this individual event, we will identify strategies of action that center the needs and assets of people residing in the Majority World when it comes to designing, upholding or challenging the frameworks enabling contemporary platforms.