A method comprising receiving by an arbitrary query engine a user request to perform a query associated with user data including first data and second data; partitioning the query into first and second sub-queries; providing the first sub-query to a first service provider interface (SPI) integrated into a first service configured to operate on the first data in a first datastore, the first SPI including a common interface component configured based on a uniform access specification to facilitate external communication between the arbitrary query engine and the first SPI, and the first SPI including a first service interface component configured to transform between the uniform access specification and a first service data specification and to facilitate internal data management; obtaining from the first datastore the first data formatted according to the first service data specification; transforming the first data; and providing the transformed first data to the arbitrary query engine.