diff --git a/pkgs/development/python-modules/calysto-scheme/default.nix b/pkgs/development/python-modules/calysto-scheme/default.nix
index a61c2ec18ff2..8a4d100cd414 100644
--- a/pkgs/development/python-modules/calysto-scheme/default.nix
+++ b/pkgs/development/python-modules/calysto-scheme/default.nix
@@ -1,9 +1,12 @@
 { lib
-, python3
+, buildPythonPackage
 , fetchFromGitHub
+, metakernel
+, pytestCheckHook
+, yasi
 }:
 
-python3.pkgs.buildPythonPackage rec {
+buildPythonPackage rec {
   pname = "calysto-scheme";
   version = "1.4.7";
   format = "setuptools";
@@ -15,11 +18,15 @@ python3.pkgs.buildPythonPackage rec {
     hash = "sha256-5InImTbucggjf/tl8K31ZtLrwu5hqvggl7sYb0eqIEg=";
   };
 
-  propagatedBuildInputs = with python3.pkgs; [
+  propagatedBuildInputs = [
     yasi
     metakernel
   ];
 
+  nativeCheckInputs = [
+    pytestCheckHook
+  ];
+
   pythonImportsCheck = [ "calysto_scheme" ];
 
   meta = with lib; {
diff --git a/pkgs/development/python-modules/calysto/default.nix b/pkgs/development/python-modules/calysto/default.nix
index 81a10066d29b..54f7eb044b7f 100644
--- a/pkgs/development/python-modules/calysto/default.nix
+++ b/pkgs/development/python-modules/calysto/default.nix
@@ -1,9 +1,14 @@
 { lib
-, python3
+, buildPythonPackage
 , fetchFromGitHub
+, metakernel
+, svgwrite
+, ipywidgets
+, cairosvg
+, numpy
 }:
 
-python3.pkgs.buildPythonPackage rec {
+buildPythonPackage rec {
   pname = "calysto";
   version = "1.0.6";
   format = "setuptools";
@@ -15,7 +20,7 @@ python3.pkgs.buildPythonPackage rec {
     hash = "sha256-lr/cHFshpFs/PGMCsa3FKMRPTP+eE9ziH5XCpV+KzO8=";
   };
 
-  propagatedBuildInputs = with python3.pkgs; [
+  propagatedBuildInputs = [
     metakernel
     svgwrite
     ipywidgets
@@ -23,7 +28,7 @@ python3.pkgs.buildPythonPackage rec {
     numpy
   ];
 
-  # Tests are failing not because of Nix.
+  # there are no tests
   doCheck = false;
 
   pythonImportsCheck = [ "calysto" ];
diff --git a/pkgs/development/python-modules/yasi/default.nix b/pkgs/development/python-modules/yasi/default.nix
index 00eb1937fe8c..8759e499b639 100644
--- a/pkgs/development/python-modules/yasi/default.nix
+++ b/pkgs/development/python-modules/yasi/default.nix
@@ -1,9 +1,11 @@
 { lib
-, python3
+, buildPythonApplication
+, colorama
 , fetchFromGitHub
+, pytestCheckHook
 }:
 
-python3.pkgs.buildPythonApplication rec {
+buildPythonApplication rec {
   pname = "yasi";
   version = "2.1.2";
   format = "setuptools";
@@ -15,10 +17,14 @@ python3.pkgs.buildPythonApplication rec {
     hash = "sha256-xKhVTmh/vrtBkatxtk8R4yqbGroH0I+xTKNYUpuikt4=";
   };
 
-  propagatedBuildInputs = with python3.pkgs; [
+  propagatedBuildInputs = [
     colorama
   ];
 
+  nativeBuildInputs = [
+    pytestCheckHook
+  ];
+
   postPatch = ''
     substituteInPlace setup.py \
       --replace "test.test_yasi" "tests.test_yasi"
diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index 13e5f75c3dd0..92b6f35efe16 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -12856,7 +12856,7 @@ self: super: with self; {
 
   yarl = callPackage ../development/python-modules/yarl { };
 
-  yasi = toPythonModule (callPackage ../development/python-modules/yasi { });
+  yasi = callPackage ../development/python-modules/yasi { };
 
   yaspin = callPackage ../development/python-modules/yaspin { };