This is how Neo4j clustering works, FWIW. Client gets a “bookmark” - basically an index into the RAFT log - and can opt to include that when querying secondarie

This is how Neo4j clustering works, FWIW. Client gets a “bookmark” - basically an index into the RAFT log - and can opt to include that when querying secondaries, who will block. I imagine variations of this are quite common, vector clocks as distributed barriers.