@@ -14,13 +14,14 @@
  * LICENSE.GPLv2 or LICENSE.GPLv3 respectively included in the packaging of this
  * file.
  */
 
 #import "OFObject.h"
-#import "OFSerialization.h"
+#import "OFASN1DERRepresentation.h"
 #import "OFJSONRepresentation.h"
 #import "OFMessagePackRepresentation.h"
+#import "OFSerialization.h"
 
 OF_ASSUME_NONNULL_BEGIN
 
 /*!
  * @class OFNull OFNull.h ObjFW/OFNull.h
@@ -27,15 +28,15 @@
  *
  * @brief A class for representing null values in collections.
  */
 OF_SUBCLASSING_RESTRICTED
 @interface OFNull: OFObject <OFCopying, OFSerialization, OFJSONRepresentation,
-    OFMessagePackRepresentation>
+    OFMessagePackRepresentation, OFASN1DERRepresentation>
 /*!
  * @brief Returns an OFNull singleton.
  *
  * @return An OFNull singleton
  */
 + (OFNull *)null;
 @end
 
 OF_ASSUME_NONNULL_END