Abstract: Embodiments are directed to improving social network applications using the power of the blockchain (or other repository of facts as a service). The embodiments include methods and systems that register users with a social network application coupled to the blockchain, including providing respective user identifiers recorded in the blockchain. The methods and systems, for each user, configure a set of verification parameters enabled to filter the participation of the respective user identifier in operations. The methods and systems initiate, by a querying user, an operation that causes the social network application to: (a) query the blockchain to locate attested-to facts specific to user identifiers of the registered users and (b) filter participation of at least one user identifier in the operation based on the attested-to facts meeting the verification parameters.