diff --git a/pkgs/development/python-modules/traits/default.nix b/pkgs/development/python-modules/traits/default.nix
new file mode 100644
index 00000000000..380827e6488
--- /dev/null
+++ b/pkgs/development/python-modules/traits/default.nix
@@ -0,0 +1,39 @@
+{ stdenv
+, buildPythonPackage
+, fetchPypi
+, python
+, pytest
+, numpy
+, isPy33
+}:
+
+buildPythonPackage rec {
+  pname = "traits";
+  version = "4.6.0";
+
+  src = fetchPypi {
+    inherit pname version;
+    sha256 = "0w43qv36wnrimlh0nzzgg81315a18yza3vk494wqxf1l19g390jx";
+  };
+
+  # Use pytest because its easier to discover tests
+  buildInputs = [ pytest ];
+  propagatedBuildInputs = [ numpy ];
+
+  checkPhase = ''
+    py.test $out/${python.sitePackages}
+  '';
+
+  # Test suite is broken for 3.x on latest release
+  # https://github.com/enthought/traits/issues/187
+  # https://github.com/enthought/traits/pull/188
+  # Furthermore, some tests fail due to being in a chroot
+  doCheck = isPy33;
+
+  meta = with stdenv.lib; {
+    description = "Explicitly typed attributes for Python";
+    homepage = https://pypi.python.org/pypi/traits;
+    license = "BSD";
+  };
+
+}
diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index ea5cbfcbd7b..ae6844a1072 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -3995,36 +3995,7 @@ in {
 
   smmap2 = callPackage ../development/python-modules/smmap2 { };
 
-  traits = buildPythonPackage rec {
-    name = "traits-${version}";
-    version = "4.6.0";
-
-    src = pkgs.fetchurl {
-      url = "mirror://pypi/t/traits/${name}.tar.gz";
-      sha256 = "0w43qv36wnrimlh0nzzgg81315a18yza3vk494wqxf1l19g390jx";
-    };
-
-    # Use pytest because its easier to discover tests
-    buildInputs = with self; [ pytest ];
-    checkPhase = ''
-      py.test $out/${python.sitePackages}
-    '';
-
-    # Test suite is broken for 3.x on latest release
-    # https://github.com/enthought/traits/issues/187
-    # https://github.com/enthought/traits/pull/188
-    # Furthermore, some tests fail due to being in a chroot
-    doCheck = isPy33;
-
-    propagatedBuildInputs = with self; [ numpy ];
-
-    meta = {
-      description = "Explicitly typed attributes for Python";
-      homepage = https://pypi.python.org/pypi/traits;
-      license = "BSD";
-    };
-  };
-
+  traits = callPackage ../development/python-modules/traits { };
 
   transaction = callPackage ../development/python-modules/transaction { };