Fluent is a programming framework for building extremely low-latency applications that scale up across cores and servers. It provides a familiar dataflow programming interface but offers performance independence across cores, with asynchronous execution and a library of composable, coordination-free dataflow operators. Despite the asynchrony inherent in its execution, Fluent’s dataflow abstraction provides the data lineage to ensure debuggability and replay across cores and servers. And Fluent’s underpinnings in logic and lattices allow for compiler checks to avoid coordination unless is it necessary.