diff --git a/JSONFile.h b/JSONFile.h
index 2d1eef8..3f7c112 100644
--- a/JSONFile.h
+++ b/JSONFile.h
@@ -19,12 +19,12 @@ namespace coreutils {
       JSONFile(ZString path): JString(), File(path, O_RDWR, 0644) {
 
       }
-
+      
       virtual ~JSONFile() {
          write(*this);
       }
 
-
+      void changed(ZString key, ZString value) overide;
 
    };
 
diff --git a/JString.cpp b/JString.cpp
index f13a080..de91bc8 100644
--- a/JString.cpp
+++ b/JString.cpp
@@ -216,5 +216,7 @@ namespace coreutils {
       }
       return output;      
    }
-      
+
+   void JString::changed(ZString key, ZString value) {}
+   
 }
diff --git a/JString.h b/JString.h
index 3897af6..0890c0d 100644
--- a/JString.h
+++ b/JString.h
@@ -69,6 +69,7 @@ namespace coreutils {
 
 	 Proxy& operator=(coreutils::MString value) {	    
 	    jstring.set(key, value);
+	    jstring.changed(key, value);
 	    return *this;
 	 }
 
@@ -84,6 +85,8 @@ namespace coreutils {
       JString & operator=(coreutils:: ZString value);
 
       MString pretty();
+
+      virtual void changed(ZString key, ZString value);
       
     private:
       void removeWhitespace();
diff --git a/testing/jstring_test b/testing/jstring_test
index 92a2946..f131c2b 100755
Binary files a/testing/jstring_test and b/testing/jstring_test differ