AMD is backing the CryEgine with their Mantle integration and NVidia is backing UE4 with GameWorks - I know Epic wouldn’t want to lose a user base because of video hardware favoritism so i’m sure the integration will work on both platforms - Judging from the past i’m pretty sure Epic and NVidia are working on the integration, DayLight which uses UE4 uses GameWorks libraries even though the game itself looked horrible the libraries were in there.