diff --git a/pkgs/by-name/py/pyxel/package.nix b/pkgs/by-name/py/pyxel/package.nix
index 4c9cd40682ff7..78880ebf342f6 100644
--- a/pkgs/by-name/py/pyxel/package.nix
+++ b/pkgs/by-name/py/pyxel/package.nix
@@ -56,7 +56,7 @@ python3.pkgs.buildPythonApplication rec {
   env.NIX_CFLAGS_COMPILE = "-I${lib.getDev SDL2}/include/SDL2";
 
   # Tests can't use the display
-  dontCheck = true;
+  doCheck = false;
 
   pythonImportsCheck = [
     "pyxel"
diff --git a/pkgs/development/python-modules/gpt-2-simple/default.nix b/pkgs/development/python-modules/gpt-2-simple/default.nix
index 109ee08b34fe6..d8561bf346e97 100644
--- a/pkgs/development/python-modules/gpt-2-simple/default.nix
+++ b/pkgs/development/python-modules/gpt-2-simple/default.nix
@@ -4,6 +4,7 @@
   fetchFromGitHub,
   regex,
   requests,
+  setuptools,
   tqdm,
   numpy,
   toposort,
@@ -13,7 +14,7 @@
 buildPythonPackage rec {
   pname = "gpt-2-simple";
   version = "0.8.1";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "minimaxir";
@@ -22,6 +23,8 @@ buildPythonPackage rec {
     hash = "sha256-WwD4sDcc28zXEOISJsq8e+rgaNrrgIy79Wa4J3E7Ovc=";
   };
 
+  build-system = [ setuptools ];
+
   propagatedBuildInputs = [
     regex
     requests
@@ -31,7 +34,7 @@ buildPythonPackage rec {
     tensorflow
   ];
 
-  dontCheck = true; # no tests in upstream
+  doCheck = false; # no tests in upstream
 
   meta = with lib; {
     description = "Easily retrain OpenAI's GPT-2 text-generating model on new texts";
diff --git a/pkgs/development/python-modules/kaitaistruct/default.nix b/pkgs/development/python-modules/kaitaistruct/default.nix
index 077d24f2462e3..24807eacdc001 100644
--- a/pkgs/development/python-modules/kaitaistruct/default.nix
+++ b/pkgs/development/python-modules/kaitaistruct/default.nix
@@ -5,6 +5,7 @@
   fetchFromGitHub,
   brotli,
   lz4,
+  setuptools,
 }:
 
 let
@@ -18,7 +19,7 @@ in
 buildPythonPackage rec {
   pname = "kaitaistruct";
   version = "0.10";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchPypi {
     inherit pname version;
@@ -30,13 +31,14 @@ buildPythonPackage rec {
     sed '32ipackages = kaitai/compress' -i setup.cfg
   '';
 
+  build-system = [ setuptools ];
+
   propagatedBuildInputs = [
     brotli
     lz4
   ];
 
-  # no tests
-  dontCheck = true;
+  doCheck = false; # no tests in upstream
 
   pythonImportsCheck = [
     "kaitaistruct"