Community-driven digital therapeutics (DTx) represent an emergent form of health innovation where patients, caregivers, and peer networks collectively develop digital tools to manage chronic illnesses outside formal clinical and commercial structures. Rather than lobbying for change through traditional top-down mechanisms, these groups enact prefigurative politics: they build in the present the horizontal, participatory, and patient-empowered models of care they seek for the future. Focusing primarily on the #WeAreNotWaiting movement for open-source diabetes technologies, this chapter traces how grassroots innovation has reshaped both clinical outcomes and regulatory debates. Users of open-source automated insulin delivery systems have demonstrated tangible health benefits such as improved glycaemic control and quality of life while simultaneously challenging conventional governance models of digital health. Alongside, similar initiatives in respiratory health and mental health illustrate that distributed, community-centred innovation is a growing phenomenon. Nevertheless, critical tensions persist issues of equity, regulation, commercialisation, and sustainability continuously shape the possibilities and limits of such grassroots DTx. By examining these experiments in "chronic living" this chapter argues that prefigurative, user-led digital health offers a powerful, if contested, alternative trajectory for health systems, demonstrating that participatory, open-source care can be lived and expanded today rather than deferred to an imagined future.