diff --git a/packages/file/lib/src/forwarding/forwarding_directory.dart b/packages/file/lib/src/forwarding/forwarding_directory.dart
index 1374963..1c441d1 100644
--- a/packages/file/lib/src/forwarding/forwarding_directory.dart
+++ b/packages/file/lib/src/forwarding/forwarding_directory.dart
@@ -9,7 +9,7 @@
 
 /// A directory that forwards all methods and properties to a delegate.
 abstract class ForwardingDirectory<T extends Directory>
-    extends ForwardingFileSystemEntity<T, io.Directory> implements Directory {
+    implements ForwardingFileSystemEntity<T, io.Directory>, Directory {
   @override
   T wrap(io.Directory delegate) => wrapDirectory(delegate);
 
diff --git a/packages/file/lib/src/forwarding/forwarding_file.dart b/packages/file/lib/src/forwarding/forwarding_file.dart
index cf671f8..ef99d92 100644
--- a/packages/file/lib/src/forwarding/forwarding_file.dart
+++ b/packages/file/lib/src/forwarding/forwarding_file.dart
@@ -9,8 +9,8 @@
 import 'package:file/file.dart';
 
 /// A file that forwards all methods and properties to a delegate.
-abstract class ForwardingFile extends ForwardingFileSystemEntity<File, io.File>
-    implements File {
+abstract class ForwardingFile
+    implements ForwardingFileSystemEntity<File, io.File>, File {
   @override
   ForwardingFile wrap(io.File delegate) => wrapFile(delegate);
 
diff --git a/packages/file/lib/src/forwarding/forwarding_link.dart b/packages/file/lib/src/forwarding/forwarding_link.dart
index f88a08d..19a3819 100644
--- a/packages/file/lib/src/forwarding/forwarding_link.dart
+++ b/packages/file/lib/src/forwarding/forwarding_link.dart
@@ -8,8 +8,8 @@
 import 'package:file/file.dart';
 
 /// A link that forwards all methods and properties to a delegate.
-abstract class ForwardingLink extends ForwardingFileSystemEntity<Link, io.Link>
-    implements Link {
+abstract class ForwardingLink
+    implements ForwardingFileSystemEntity<Link, io.Link>, Link {
   @override
   ForwardingLink wrap(io.Link delegate) => wrapLink(delegate);