There are today many examples of collaborations between amateurs and professional scientists: in the fields of natural history, astronomy, epidemiology, medicine, biology, environmental science, and informatics. To describe these collaborations, there is a plethora of terms used such as ‘co-production,’ ‘participation’, ‘citizen science’, or ‘community-based research.’ But rather than using and reiterating these notions, I will problematize the very notion of participation. To do so, I will draw upon three current examples: do-it-yourself biology, the auto-construction of agricultural tools, and open source ecology. I will argue that the ‘fabric of participation’ deserves more attention. First, we need to focus on the sites of participation: in what kinds of places, buildings, and spaces does participation happen (be it laboratories, workshops, garages, field-work sites, etc.)? Second, we need to focus not only on results but also on processes: how is participation produced, tinkered, constructed? Third, what is the texture of this participation? What kinds of tools, materialities and networks are made and mobilised? Domesticating science and experimenting with biology and ecology outside institutional frames raises interesting questions and debates about the boundaries, sociabilities and materialities of scientific practices.