- (NSSet*) keysChanged: (NSDictionary<NSString*, NSObject*>*) keyValues error: (NSError**) error;
- (bool) ensurePeerRegistration: (NSError**) error;
+
+- (NSSet<NSString*>*) syncWithPeers: (NSSet<NSString*>*) peerIDs backups: (NSSet<NSString*>*) backupPeerIDs error: (NSError**) error;
- (bool) syncWithAllPeers: (NSError**) error;
@end