Apache NiFi: NiagaraFiles, flow based programming

Apache NiFi - Wikipedia

Apache NiFi is a software project from the Apache Software Foundation designed to automate the flow of data between software systems. It is based on the "NiagaraFiles" software previously developed by the NSA, which is also the source of a part of its present name – NiFi.
Flow-based programming - Wikipedia

flow-based programming (FBP) is a programming paradigm that defines applications as networks of "black box" processes, which exchange data across predefined connections by message passing, where the connections are specified externally to the processes. These black box processes can be reconnected endlessly to form different applications without having to be changed internally. FBP is thus naturally component-oriented.

FBP is a particular form of dataflow programming based on bounded buffers, information packets with defined lifetimes, named ports, and separate definition of connections.