International audienceBig Data applications are rapidly moving from a batch-oriented execution model to a streaming execution model in order to extract value from the data in real-time. However, processing live data alone is often not enough: in many cases, such applications need to combine the live data with previously archived data to increase the quality of the extracted insights. Current streaming-oriented runtimes and middlewares are not flexible enough to deal with this trend, as they address ingestion (collection and pre-processing of data streams) and persistent storage (archival of intermediate results) using separate services. This separation often leads to I/O redundancy (e.g., write data twice to disk or transfer data twice over...