diff --git a/lib/fast_jsonapi/multi_to_json.rb b/lib/fast_jsonapi/multi_to_json.rb
index 108579e..7917edb 100644
--- a/lib/fast_jsonapi/multi_to_json.rb
+++ b/lib/fast_jsonapi/multi_to_json.rb
@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require 'logger'
+
 # Usage:
 #   class Movie
 #     def to_json(payload)