diff --git a/pkgs/development/python-modules/aioprocessing/default.nix b/pkgs/development/python-modules/aioprocessing/default.nix
index 04963f1d09b1..50e4140c183e 100644
--- a/pkgs/development/python-modules/aioprocessing/default.nix
+++ b/pkgs/development/python-modules/aioprocessing/default.nix
@@ -1,13 +1,13 @@
 { lib
 , buildPythonPackage
 , fetchPypi
-, pythonAtLeast
+, pythonOlder
 }:
 
 buildPythonPackage rec {
   pname = "aioprocessing";
   version = "1.1.0";
-  disabled = !(pythonAtLeast "3.4");
+  disabled = pythonOlder "3.4";
 
   src = fetchPypi {
     inherit pname version;
@@ -17,6 +17,8 @@ buildPythonPackage rec {
   # Tests aren't included in pypi package
   doCheck = false;
 
+  pythonImportsCheck = [ "aioprocessing" ];
+
   meta = {
     description = "A library that integrates the multiprocessing module with asyncio";
     homepage = "https://github.com/dano/aioprocessing";
diff --git a/pkgs/development/python-modules/inform/default.nix b/pkgs/development/python-modules/inform/default.nix
index 9f78d86a2be6..2397c0bc4db6 100644
--- a/pkgs/development/python-modules/inform/default.nix
+++ b/pkgs/development/python-modules/inform/default.nix
@@ -2,8 +2,6 @@
 , arrow
 , six
 , hypothesis
-, pytest
-, pytest-runner
 , pytestCheckHook
 }:
 
@@ -18,13 +16,18 @@ buildPythonPackage rec {
     sha256 = "114cyff00j9r7qm2ld4w1a4kklr5gx570vk67p56gpr2553dkmly";
   };
 
-  nativeBuildInputs = [ pytest-runner ];
+  postPatch = ''
+    substituteInPlace setup.py \
+      --replace "pytest-runner>=2.0" ""
+  '';
+
   propagatedBuildInputs = [ arrow six ];
 
-  checkInputs = [ pytest hypothesis ];
-  checkPhase = ''
+  checkInputs = [ pytestCheckHook hypothesis ];
+  preCheck = ''
     patchShebangs test.doctests.py test.inform.py
-    ./test.doctests.py && ./test.inform.py && pytest
+    ./test.doctests.py
+    ./test.inform.py
   '';
 
   meta = with lib; {
diff --git a/pkgs/development/python-modules/jupyter-repo2docker/default.nix b/pkgs/development/python-modules/jupyter-repo2docker/default.nix
index 7597df0d76aa..1b352f1e24c9 100644
--- a/pkgs/development/python-modules/jupyter-repo2docker/default.nix
+++ b/pkgs/development/python-modules/jupyter-repo2docker/default.nix
@@ -1,4 +1,4 @@
-{ lib, buildPythonPackage, fetchPypi, pythonAtLeast
+{ lib, buildPythonPackage, fetchPypi, pythonOlder
 , docker
 , escapism
 , jinja2
@@ -14,7 +14,7 @@
 buildPythonPackage rec {
   version = "2021.3.0";
   pname = "jupyter-repo2docker";
-  disabled = !(pythonAtLeast "3.4");
+  disabled = pythonOlder "3.4";
 
   src = fetchPypi {
     inherit pname version;