Customized Internet-of-Things data packaging and brokering

A data-brokerage service that facilitates data sharing between Internet-of-Things (IoT) platforms via peer-to-peer connections is described. In various embodiments, the data-brokerage service receives, from an IoT platform acting as data consumer, a selection of data fields included in a plurality of data streams provided from a plurality of respective IoT platforms acting as data producers. Responsive to the selection, the data-brokerage service causes the plurality of data-producer platforms to stream at least the selected data fields of the plurality of data streams to the data-consumer platform, and causes the data-consumer platform to combine the streamed data fields received from the plurality of data-producer platforms into a single target data stream.