Describing the attributes and characteristics has an important place in the ethnographic study of information infrastructure. Yet, decentralised information infrastructure does not have a clearly defined “ethnography”, by which to describe its unique attributes. This piece draws on historical research on the ‘cypherpunk mailing list’ archives to form a descriptive basis of the unique attributes of decentralised information infrastructure for ethnographic studies. The unique characteristics of decentralised information infrastructure outlined are: decentralised, autonomous, participatory, permissionless, ad hoc, encrypted, full-stack, modular, migratable, scalable, requires a community, trust gradient, and evolutionary. These characteristics form a basis for further ethnographic enquiry into the opportunities and limitations of decentralised information infrastructure in society.