The paper analyses global online labour platforms (OLPs) through the lens of the Expansive-Restrictive Learning Environments framework. The framework articulates a set of structural factors that enable or constrain workplace learning and development. The paper draws on multistakeholder, mixed-method empirical data to illustrate how OLPs are emerging as learning environments, where new and reconfigured skills, learning practices, and new forms of learning support emerge in response to the radically distributed and fragmented nature of this work. Against portrayals of OLPs as places of deskilling work devoid of learning opportunities, the paper contributes a more nuanced understanding of the duality of OLPs as simultaneously restrictive and expansive. Three dualities of OLPs emerge from the study: (i) their espoused vision restricts organisational support for workforce development, yet stimulates self-directed learning; (ii) their enacted workplace curriculum is patchy and opaque, yet offers novel structural features supporting learning and development; (iii) workplace learning practices in OLPs are autonomous, yet not atomised. The paper illustrates how structure and individual agency interact in OLPs to create and configure learning opportunities for workers and informs practitioners about the current learning and development features and practices in OLPs.