MongoDB Charts now allows data source owners to attach aggregation pipelines directly to a data source, giving them the power to pre-process their data before it's used for visualization. This feature provides a third option for handling complex or sensitive data, in addition to creating views using the mongo shell or adding chart-level pipelines. With this update, users can edit and share aggregation pipelines across charts, join data from multiple collections, and ensure consistent data processing logic for all charts using a specific data source.