diff --git a/pkgs/development/python-modules/jupytext/default.nix b/pkgs/development/python-modules/jupytext/default.nix
index 66e792276971..ae6796825f1c 100644
--- a/pkgs/development/python-modules/jupytext/default.nix
+++ b/pkgs/development/python-modules/jupytext/default.nix
@@ -1,41 +1,33 @@
-{ lib
-, buildPythonPackage
-, fetchPypi
-, testfixtures
-, pyyaml
+{ lib, buildPythonPackage, fetchPypi, isPy27
 , mock
 , nbformat
 , pytest
+, pyyaml
 }:
 
 buildPythonPackage rec {
   pname = "jupytext";
-  version = "1.1.7";
+  version = "1.2.1";
 
   src = fetchPypi {
     inherit pname version;
-    sha256 = "0g365j22gbmq4x60l06id5930aywzy1dx2s25109nqq2l2cxc7ws";
+    sha256 = "05vwxgjh7pzxgdzj0775562bfps8j7w3p7dcf1zfh169whqw9vg8";
   };
 
   propagatedBuildInputs = [
     pyyaml
     nbformat
-    testfixtures
-  ];
+  ] ++ lib.optionals isPy27 [ mock ]; # why they put it in install_requires, who knows
+
   checkInputs = [
     pytest
   ];
-  # setup.py checks for those even though they're not needed at runtime (only
-  # for tests), thus not propagated
-  buildInputs = [
-    mock
-    pytest
-  ];
 
   # requires test notebooks which are not shipped with the pypi release
+  # also, pypi no longer includes tests
   doCheck = false;
   checkPhase = ''
-    py.test
+    pytest
   '';
 
   meta = with lib; {