diff --git a/pkgs/development/python-modules/backports_functools_lru_cache/default.nix b/pkgs/development/python-modules/backports_functools_lru_cache/default.nix
index 21920c32b4d2..680d23782f56 100644
--- a/pkgs/development/python-modules/backports_functools_lru_cache/default.nix
+++ b/pkgs/development/python-modules/backports_functools_lru_cache/default.nix
@@ -3,10 +3,7 @@
 , fetchPypi
 , setuptools-scm
 , isPy3k
-, pytest
-, pytest-black
-, pytest-flake8
-, pytest-cov
+, pytestCheckHook
 }:
 
 buildPythonPackage rec {
@@ -20,12 +17,7 @@ buildPythonPackage rec {
 
   nativeBuildInputs = [ setuptools-scm ];
 
-  checkInputs = [ pytest pytest-flake8 pytest-black pytest-cov ];
-  # ironically, they fail a linting test, and pytest.ini forces that test suite
-  checkPhase = ''
-    rm backports/functools_lru_cache.py
-    pytest -k 'not format'
-  '';
+  checkInputs = [ pytestCheckHook ];
 
   # Test fail on Python 2
   doCheck = isPy3k;
diff --git a/pkgs/development/python-modules/portend/black-19.10b0.patch b/pkgs/development/python-modules/portend/black-19.10b0.patch
deleted file mode 100644
index e781139e3192..000000000000
--- a/pkgs/development/python-modules/portend/black-19.10b0.patch
+++ /dev/null
@@ -1,13 +0,0 @@
-diff --git a/test_portend.py b/test_portend.py
-index b2de8c2..3f90276 100644
---- a/test_portend.py
-+++ b/test_portend.py
-@@ -21,7 +21,7 @@ def socket_infos():
- 
- 
- def id_for_info(info):
--    af, = info[:1]
-+    (af,) = info[:1]
-     return str(af)
- 
- 
\ No newline at end of file
diff --git a/pkgs/development/python-modules/portend/default.nix b/pkgs/development/python-modules/portend/default.nix
index a3cb25624f7a..bf84e41610cb 100644
--- a/pkgs/development/python-modules/portend/default.nix
+++ b/pkgs/development/python-modules/portend/default.nix
@@ -1,5 +1,5 @@
 { lib, buildPythonPackage, fetchPypi
-, pytest, setuptools-scm, tempora, pytest-black, pytest-cov }:
+, pytestCheckHook, setuptools-scm, tempora  }:
 
 buildPythonPackage rec {
   pname = "portend";
@@ -10,19 +10,11 @@ buildPythonPackage rec {
     sha256 = "239e3116045ea823f6df87d6168107ad75ccc0590e37242af0cc1e98c5d224e4";
   };
 
-  postPatch = ''
-    substituteInPlace pytest.ini --replace "--flake8" ""
-  '';
-
   nativeBuildInputs = [ setuptools-scm ];
 
   propagatedBuildInputs = [ tempora ];
 
-  checkInputs = [ pytest pytest-black pytest-cov ];
-
-  checkPhase = ''
-    py.test --deselect=test_portend.py::TestChecker::test_check_port_listening
-  '';
+  checkInputs = [ pytestCheckHook ];
 
   # Some of the tests use localhost networking.
   __darwinAllowLocalNetworking = true;
diff --git a/pkgs/development/python-modules/tempora/default.nix b/pkgs/development/python-modules/tempora/default.nix
index 6999655c5dc5..79b04b7ebbb2 100644
--- a/pkgs/development/python-modules/tempora/default.nix
+++ b/pkgs/development/python-modules/tempora/default.nix
@@ -1,7 +1,6 @@
 { lib, buildPythonPackage, fetchPypi
-, setuptools-scm, pytest, pytest-freezegun, freezegun, backports_unittest-mock
+, setuptools-scm, pytestCheckHook, pytest-freezegun, freezegun, backports_unittest-mock
 , six, pytz, jaraco_functools, pythonOlder
-, pytest-flake8, pytest-cov, pytest-black, pytest-mypy
 }:
 
 buildPythonPackage rec {
@@ -20,14 +19,9 @@ buildPythonPackage rec {
   propagatedBuildInputs = [ six pytz jaraco_functools ];
 
   checkInputs = [
-    pytest-freezegun pytest freezegun backports_unittest-mock
-    pytest-flake8 pytest-cov pytest-black pytest-mypy
+    pytest-freezegun pytestCheckHook freezegun backports_unittest-mock
   ];
 
-  checkPhase = ''
-    pytest
-  '';
-
   meta = with lib; {
     description = "Objects and routines pertaining to date and time";
     homepage = "https://github.com/jaraco/tempora";