diff --git a/pkgs/development/python-modules/sphinx-rtd-theme/default.nix b/pkgs/development/python-modules/sphinx-rtd-theme/default.nix
index 3ec142f14035..613f19981216 100644
--- a/pkgs/development/python-modules/sphinx-rtd-theme/default.nix
+++ b/pkgs/development/python-modules/sphinx-rtd-theme/default.nix
@@ -31,9 +31,12 @@ buildPythonPackage rec {
     sphinxcontrib-jquery
   ];
 
+  nativeBuildInputs = [
+    pythonRelaxDepsHook
+  ];
+
   nativeCheckInputs = [
     pytestCheckHook
-    pythonRelaxDepsHook
     readthedocs-sphinx-ext
   ];