diff --git a/pkgs/development/python-modules/diff-cover/default.nix b/pkgs/development/python-modules/diff-cover/default.nix
new file mode 100644
index 000000000000..7a9e1205979a
--- /dev/null
+++ b/pkgs/development/python-modules/diff-cover/default.nix
@@ -0,0 +1,57 @@
+{ lib
+, buildPythonPackage
+, chardet
+, fetchPypi
+, inflect
+, jinja2
+, jinja2_pluralize
+, pycodestyle
+, pyflakes
+, pygments
+, pylint
+, pytest-mock
+, pytestCheckHook
+, pythonOlder
+}:
+
+buildPythonPackage rec {
+  pname = "diff-cover";
+  version = "5.4.0";
+  disabled = pythonOlder "3.6";
+
+  src = fetchPypi {
+    pname = "diff_cover";
+    inherit version;
+    sha256 = "sha256-4iQ9/QcXh/lW8HE6wFZWc6Y57xhAEWu2TQnIUZJNAMs=";
+  };
+
+  propagatedBuildInputs = [
+    chardet
+    inflect
+    jinja2
+    jinja2_pluralize
+    pygments
+  ];
+
+  checkInputs = [
+    pycodestyle
+    pyflakes
+    pylint
+    pytest-mock
+    pytestCheckHook
+  ];
+
+  disabledTests = [
+    "added_file_pylint_console"
+    "file_does_not_exist"
+  ];
+
+  pythonImportsCheck = [ "diff_cover" ];
+
+  meta = with lib; {
+    description = "Automatically find diff lines that need test coverage";
+    homepage = "https://github.com/Bachmann1234/diff-cover";
+    license = licenses.asl20;
+    maintainers = with maintainers; [ dzabraev ];
+  };
+}
diff --git a/pkgs/development/python-modules/diff_cover/default.nix b/pkgs/development/python-modules/diff_cover/default.nix
deleted file mode 100644
index 7eeb378ff417..000000000000
--- a/pkgs/development/python-modules/diff_cover/default.nix
+++ /dev/null
@@ -1,46 +0,0 @@
-{ lib, buildPythonPackage, fetchPypi
-, chardet
-, inflect
-, jinja2
-, jinja2_pluralize
-, pygments
-, six
-# test dependencies
-, coverage
-, mock
-, nose
-, pycodestyle
-, pyflakes
-, pylint
-, pytest
-}:
-
-buildPythonPackage rec {
-  pname = "diff_cover";
-  version = "5.2.0";
-
-  preCheck = ''
-    export LC_ALL=en_US.UTF-8;
-  '';
-
-  src = fetchPypi {
-    inherit pname version;
-    sha256 = "a1cd54232d2e48bd4c1eabc96cfe4a8727a9a92fd2556b52ff8f65bb8adf8768";
-  };
-
-  propagatedBuildInputs = [ chardet jinja2 jinja2_pluralize pygments six inflect ];
-
-  checkInputs = [ mock coverage pytest nose pylint pyflakes pycodestyle ];
-
-  # ignore tests which try to write files
-  checkPhase = ''
-    pytest -k 'not added_file_pylint_console and not file_does_not_exist'
-  '';
-
-  meta = with lib; {
-    description = "Automatically find diff lines that need test coverage";
-    homepage = "https://github.com/Bachmann1234/diff-cover";
-    license = licenses.asl20;
-    maintainers = with maintainers; [ dzabraev ];
-  };
-}
diff --git a/pkgs/top-level/python-aliases.nix b/pkgs/top-level/python-aliases.nix
index 7ea357116233..09a77cfe6bd7 100644
--- a/pkgs/top-level/python-aliases.nix
+++ b/pkgs/top-level/python-aliases.nix
@@ -36,6 +36,7 @@ mapAliases ({
   blockdiagcontrib-cisco = throw "blockdiagcontrib-cisco is not compatible with blockdiag 2.0.0 and has been removed."; # Added 2020-11-29
   bugseverywhere = throw "bugseverywhere has been removed: Abandoned by upstream."; # Added 2019-11-27
   detox = throw "detox is no longer maintained, and was broken since may 2019"; # added 2020-07-04
+  diff_cover = diff-cover; # added 2021-07-02
   dns = dnspython; # Alias for compatibility, 2017-12-10
   faulthandler = throw "faulthandler is built into ${python.executable}";
   gitdb2 = throw "gitdb2 has been deprecated, use gitdb instead."; # added 2020-03-14
diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index f4ed5fedd16b..89cfeeeaad1d 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -1919,7 +1919,7 @@ in {
 
   dicttoxml = callPackage ../development/python-modules/dicttoxml { };
 
-  diff_cover = callPackage ../development/python-modules/diff_cover { };
+  diff-cover = callPackage ../development/python-modules/diff-cover { };
 
   diff-match-patch = callPackage ../development/python-modules/diff-match-patch { };