diff --git a/lib/rules/subsystem.js b/lib/rules/subsystem.js
index 963df24..06773a7 100644
--- a/lib/rules/subsystem.js
+++ b/lib/rules/subsystem.js
@@ -40,6 +40,7 @@ const validSubsystems = [
   'constants',
   'crypto',
   'debugger',
+  'diagnostics_channel',
   'dgram',
   'diagnostics_channel',
   'dns',