Systems and methods for processing events transmitted by an application to hashing processors executing a custom mempool protocol that is independent of the public blockchain protocol. Events transmitted by the application are hashed only into blocks with other events transmitted by the application or events with parameters satisfying a screening criterion and are not propagated to mempools of nodes that are not executing the custom mempool protocol. The blocks are appended to the blockchain according to the public blockchain protocol. Thus, application users exercise intentionality over which hashing processors process their events and which other events will be hashed into a block with the users' events.