Valentin has over 15 years of experience in designing and leading participatory projects for institutions and citizens in France and across Europe. He heads Open Source Politics, a social and solidarity economy company he co-founded in 2016 to promote the development of civic technologies based on free software and innovative collective intelligence methods. He has advised dozens of local authorities of all sizes as well as major institutions, including the EU Commission. In 2025, he co-initiated the European Democracy Data Space to connect civic technologies and increase their impact.