diff --git a/pkgs/io/lib/src/process_manager.dart b/pkgs/io/lib/src/process_manager.dart
index a126335..496c17d 100644
--- a/pkgs/io/lib/src/process_manager.dart
+++ b/pkgs/io/lib/src/process_manager.dart
@@ -72,7 +72,6 @@
   }
 
   @mustCallSuper
-  @visibleForOverriding
   void _onClosed() {}
 
   @override
diff --git a/pkgs/io/pubspec.yaml b/pkgs/io/pubspec.yaml
index 3045840..2175d5d 100644
--- a/pkgs/io/pubspec.yaml
+++ b/pkgs/io/pubspec.yaml
@@ -8,6 +8,9 @@
 environment:
   sdk: ">=1.22.0 <2.0.0"
 
+dependencies:
+  meta: ^1.0.2
+
 dev_dependencies:
   path: ^1.0.0
   test: ^0.12.0