In the French village of Saillans (1,300 inhabitants), citizens mobilize against the installation of a supermarket and the opaque management of elected officials. In 2014, they won the municipal elections and set up a radical and alternative project of governance of the village. The elected officials entrust the inhabitants with the power to carry out their municipal policy and are essentially responsible for leading and supporting the collective decision. Citizen participation is massive : a participatory event takes place every 3 to 4 days; 1 out of 2 inhabitants takes part in the experience at least once during the six years. Saillans is a changing rural territory, marked by the urban exodus and growing environmental concerns. The central political stake is the transformation of lifestyles (less carbon-intensive mobility, more grouped housing, more local and organic food, etc.). The greening of daily practices appears as an injunction to change for some and a desired and chosen transformation for others. The revision of the Local Urban Plan appears to be one of the major test : it challenges the village community to live, decide and do things together in the face of environmental changes. The experience of Saillans constitutes a real and concrete utopia, where citizen participation is the main driving force of the ecological transition. Breaking with the planning tradition and the logic of strategic projects, the people are developing a new, more improvised mode of action. They see the transition as a set in motion towards an indeterminate goal, to be built collectively along the way. They therefore combine two democratic practices, action and deliberation, based on the ethics of "doing" and "discussion". This experience informs and accelerates economic, social and political transformations, foreshadowing a possible rural "counter-anthropocene". The article offers a situated analyze, presenting (1) the intentions and practices of the municipal team of which the author was a part, (2) the trials and tribulations experienced, (3) and then an overview of the ongoing transformations. It concludes with a discussion of the transformative potential of this radical citizen experiment in social and ecological transition.