Software engineers are sedentary and need technological help for a more healthy life. Current software engineering tasks are mostly confined to the standard sedentary desktop user interface. We believe that software engineering should be restructured so that it offers a non-sedentary alternative. In this paper, we describe a new research approach, called Post-sedentary Software Engineering. Our ambition with this approach is to provide an alternative, healthier work context without decreasing productivity. We take a spatial approach to post-sedentary tool design, starting from the assumption an interactive 3D environment with appropriate metaphors is necessary for full body movement. We discuss available technologies for achieving this goal and outline four studies that incorporate the software engineering phases of code comprehension, code creation and debugging in a non-sedentary context.