diff --git a/composer.json b/composer.json
index d7558295..bc3dfba3 100644
--- a/composer.json
+++ b/composer.json
@@ -38,7 +38,8 @@
     "repositories": [
         {
             "type": "vcs",
-            "url": "https://github.com/ezyang/simpletest.git"
+            "url": "https://github.com/ezyang/simpletest.git",
+            "no-api": true
         }
     ]
 }