diff --git a/src/DebugLogger.h b/src/DebugLogger.h
index 7f63bb712e..9929011278 100644
--- a/src/DebugLogger.h
+++ b/src/DebugLogger.h
@@ -5,6 +5,8 @@
 
 #ifdef DEBUG
 
+#include "zeek-config.h"
+
 #include <stdio.h>
 #include <string>
 #include <set>
@@ -20,8 +22,9 @@
 
 #define PLUGIN_DBG_LOG(plugin, args...) zeek::detail::debug_logger.Log(plugin, args)
 
+ZEEK_FORWARD_DECLARE_NAMESPACED(Plugin, zeek, plugin);
+
 namespace zeek {
-namespace plugin { class Plugin; }
 
 // To add a new debugging stream, add a constant here as well as
 // an entry to DebugLogger::streams in DebugLogger.cc.