Computer models and simulations can present an immersive space that correlates with aspects of reality. Dominant narratives presenting computation as purely ‘objective’ data operated on by algorithms ask us to see simulations as mirrors of reality, that with increased computational power we can predict the singular future. However, as shown in the case study with Loopy, software for simulation can also act as a mediator, provide a means to make explicit certain understandings and biases that might otherwise remain hidden, and a space to model and explore these ideas. As my interview subjects show, it can be productive to engage with and interrogate simulations as discursive platforms, as representations of multiple futures that might be. Through simulating processes, designers can develop ways of envisioning and working toward those futures.