diff --git a/pkgs/development/python-modules/whoosh/default.nix b/pkgs/development/python-modules/whoosh/default.nix
index 41d8530293d0..246b3c65fc5b 100644
--- a/pkgs/development/python-modules/whoosh/default.nix
+++ b/pkgs/development/python-modules/whoosh/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, buildPythonPackage, fetchPypi, pytest }:
+{ stdenv, buildPythonPackage, fetchPypi, pytest_3 }:
 
 buildPythonPackage rec {
   pname = "Whoosh";
@@ -8,7 +8,7 @@ buildPythonPackage rec {
     sha256 = "10qsqdjpbc85fykc1vgcs8xwbgn4l2l52c8d83xf1q59pwyn79bw";
   };
 
-  checkInputs = [ pytest ];
+  checkInputs = [ pytest_3 ];
 
   # Wrong encoding
   postPatch = ''