diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index 98c618e2a02..d60575ec41f 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -1206,6 +1206,10 @@ in modules // {
     pympler coverage ]
      ++ optionals (stdenv.isDarwin) [ pkgs.clang ];
 
+    checkPhase = ''
+      py.test
+    '';
+
     meta = {
       description = "Python attributes without boilerplate";
       homepage = https://github.com/hynek/attrs;