diff --git a/lib/LambdaLog.js b/lib/LambdaLog.js
index 45379e0..80e26bd 100644
--- a/lib/LambdaLog.js
+++ b/lib/LambdaLog.js
@@ -1,6 +1,10 @@
 const EventEmitter = require('events');
 const LogMessage = require('./LogMessage');
 
+const symbols = {
+  LEVELS: Symbol('levels')
+};
+
 /**
  * @external EventEmitter
  * @see https://nodejs.org/api/events.html#events_class_eventemitter
@@ -221,4 +225,6 @@ class LambdaLog extends EventEmitter {
   }
 }
 
+LambdaLog.symbols = symbols;
+
 module.exports = LambdaLog;