diff --git a/src/document.cpp b/src/document.cpp
index 9716080..fbe0216 100644
--- a/src/document.cpp
+++ b/src/document.cpp
@@ -38,6 +38,11 @@ using std::istringstream;
 using std::string;
 using std::move;
 
+bool operator !=(const Item &a, const Item &b)
+{
+    return a.guid != b.guid;
+}
+
 Document::Document(Config &cfg)
     : _cfg{cfg}
     , _profile{cfg.data}
diff --git a/src/document.hpp b/src/document.hpp
index 325015e..6dd842f 100644
--- a/src/document.hpp
+++ b/src/document.hpp
@@ -42,6 +42,8 @@ struct Item
     string guid;
     string link;
     string title;
+
+    friend bool operator !=(const Item &a, const Item &b);
 };
 
 /*!