diff --git a/test/fixtures/model/extension/uml.json b/test/fixtures/model/shadow.json
similarity index 50%
rename from test/fixtures/model/extension/uml.json
rename to test/fixtures/model/shadow.json
index 4c992b7..0b69981 100644
--- a/test/fixtures/model/extension/uml.json
+++ b/test/fixtures/model/shadow.json
@@ -1,7 +1,7 @@
 {
-  "name": "UML",
-  "uri": "http://www.omg.org/spec/UML/20131001",
-  "prefix": "uml",
+  "name": "Shadow",
+  "uri": "http://shadow",
+  "prefix": "s",
   "types": [
     {
       "name": "Element",
@@ -9,7 +9,7 @@
     },
     {
       "name": "NamedElement",
-      "superClass": [ "uml:Element" ]
+      "superClass": [ "s:Element" ]
     }
   ]
 }
\ No newline at end of file
diff --git a/test/spec/extension.js b/test/spec/extension.js
index 1692002..b10f06d 100644
--- a/test/spec/extension.js
+++ b/test/spec/extension.js
@@ -10,34 +10,36 @@ describe('extension', function() {
   var createModel = createModelBuilder('test/fixtures/model/');
 
 
-  describe('built in name shadowing', function() {
+  describe('types', function() {
 
-    it('should shadow <Element>', function() {
+    describe('built-in shadowing', function() {
 
       // given
-      var model = createModel([ 'extension/uml' ]);
+      var model = createModel([ 'shadow' ]);
 
-      // when
-      var element = model.create('uml:Element');
 
-      // then
-      expect(element).to.exist;
-      expect(element.$instanceOf('uml:Element')).to.be.true;
-    });
+      it('should shadow <Element>', function() {
 
+        // when
+        var element = model.create('s:Element');
 
-    it('should shadow <Element> in inheritance hierarchy', function() {
+        // then
+        expect(element).to.exist;
+        expect(element.$instanceOf('s:Element')).to.be.true;
+      });
 
-      // given
-      var model = createModel([ 'extension/uml' ]);
 
-      // when
-      var element = model.create('uml:NamedElement');
+      it('should shadow <Element> in inheritance hierarchy', function() {
+
+        // when
+        var element = model.create('s:NamedElement');
+
+        // then
+        expect(element).to.exist;
+        expect(element.$instanceOf('s:Element')).to.be.true;
+        expect(element.$instanceOf('s:NamedElement')).to.be.true;
+      });
 
-      // then
-      expect(element).to.exist;
-      expect(element.$instanceOf('uml:Element')).to.be.true;
-      expect(element.$instanceOf('uml:NamedElement')).to.be.true;
     });
 
   });