A boundary layer ingestion engine includes a fan section configured to extend into a boundary layer of a full annulus of an aft end of a fuselage of an aircraft. The fan section includes a first fan stage and a second fan stage. The boundary layer ingestion engine also includes a differential planetary gear system is operable to transform rotation of an input shaft into counter rotation of a first shaft coupled to the first fan stage and a second shaft coupled to the second fan stage. The boundary layer ingestion engine further includes a motor operable to drive rotation of the input shaft.