The notion that the future has a ‘shape’ is a deep-rooted construct, the cornerstone of how chance is mediated, for example through the ‘distributions’ of probability theory. Algorithmic prediction, via machine learning, builds on these shapes and amplifies their complexity and authority. While the problematic effects of this predictive regime and the preemptive politics it supports are objects of concern for scholars and practitioners across the humanities, social sciences, art, and philosophy, design is surprisingly disengaged from this conversation. Instead, it is either concerned with data visualization, often without questioning its positivist ontology, or with ‘seamless’ non-interfaces which effectively seek to remove choice. Against this backdrop, our proposal brings together design theory and design practice to interrogate current modes of algorithmic prediction and the construction of subjectivity enabled by ‘choice design’. Our designed artifacts are diagrams to think through practice about the shape(s) of the possible. Rather than designing predictable futures, we aim to use diagram-making to expose and reframe choice design. These design artifacts - initial and ongoing experiments in mapping YouTube recommendations - are a series of computational diagrams that weave together the tools of computational prediction, critical design practice, and theory.