diff --git a/pkgs/by-name/r1/r128gain/package.nix b/pkgs/by-name/r1/r128gain/package.nix
index 4c0ba8d99749..f487be2b4cfd 100644
--- a/pkgs/by-name/r1/r128gain/package.nix
+++ b/pkgs/by-name/r1/r128gain/package.nix
@@ -11,7 +11,7 @@
 python3Packages.buildPythonApplication rec {
   pname = "r128gain";
   version = "1.0.7";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "desbma";
@@ -26,12 +26,15 @@ python3Packages.buildPythonApplication rec {
     })
   ];
 
-  propagatedBuildInputs = with python3Packages; [
+  build-system = with python3Packages; [ setuptools ];
+
+  dependencies = with python3Packages; [
     crcmod
     ffmpeg-python
     mutagen
     tqdm
   ];
+
   nativeCheckInputs = with python3Packages; [
     requests
     sox
@@ -41,6 +44,8 @@ python3Packages.buildPythonApplication rec {
   # sandbox to be disabled.
   doCheck = false;
 
+  pythonImportsCheck = [ "r128gain" ];
+
   passthru.updateScript = gitUpdater { };
 
   meta = with lib; {
diff --git a/pkgs/by-name/ra/raiseorlaunch/package.nix b/pkgs/by-name/ra/raiseorlaunch/package.nix
index 80d5dba11cea..f1a8a9d51bab 100644
--- a/pkgs/by-name/ra/raiseorlaunch/package.nix
+++ b/pkgs/by-name/ra/raiseorlaunch/package.nix
@@ -7,14 +7,15 @@
 python3Packages.buildPythonApplication rec {
   pname = "raiseorlaunch";
   version = "2.3.5";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchPypi {
     inherit pname version;
     hash = "sha256-L/hu0mYCAxHkp5me96a6HlEY6QsuJDESpTNhlzVRHWs=";
   };
 
-  nativeBuildInputs = [ python3Packages.setuptools-scm ];
+  build-system = with python3Packages; [ setuptools ];
+
   pythonPath = with python3Packages; [ i3ipc ];
 
   # no tests
diff --git a/pkgs/by-name/rd/rdiff-backup/package.nix b/pkgs/by-name/rd/rdiff-backup/package.nix
index 7045656a10c8..facc5b257e8e 100644
--- a/pkgs/by-name/rd/rdiff-backup/package.nix
+++ b/pkgs/by-name/rd/rdiff-backup/package.nix
@@ -12,22 +12,27 @@ in
 pypkgs.buildPythonApplication rec {
   pname = "rdiff-backup";
   version = "2.2.6";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchPypi {
     inherit pname version;
     hash = "sha256-0HeDVyZrxlE7t/daRXCymySydgNIu/YHur/DpvCUWM8";
   };
 
-  nativeBuildInputs = with pypkgs; [ setuptools-scm ];
+  build-system = with pypkgs; [
+    setuptools
+    setuptools-scm
+  ];
 
   buildInputs = [ librsync ];
 
-  propagatedBuildInputs = with pypkgs; [ pyyaml ];
+  dependencies = with pypkgs; [ pyyaml ];
 
   # no tests from pypi
   doCheck = false;
 
+  pythonImportsCheck = [ "rdiff_backup" ];
+
   meta = with lib; {
     description = "Backup system trying to combine best a mirror and an incremental backup system";
     homepage = "https://rdiff-backup.net";
diff --git a/pkgs/by-name/re/redfishtool/package.nix b/pkgs/by-name/re/redfishtool/package.nix
index 51a1c781d4a8..029617a616a9 100644
--- a/pkgs/by-name/re/redfishtool/package.nix
+++ b/pkgs/by-name/re/redfishtool/package.nix
@@ -10,18 +10,22 @@ let
 in
 python3.pkgs.buildPythonApplication {
   inherit pname version;
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchPypi {
     inherit pname version;
     hash = "sha256-X/G6osOHCBidKZG/Y2nmHadifDacJhjBIc7WYrUCPn8=";
   };
 
+  build-system = with python3.pkgs; [ setuptools ];
+
   propagatedBuildInputs = with python3.pkgs; [
     requests
     python-dateutil
   ];
 
+  pythonImportsCheck = [ "redfishtoollib" ];
+
   meta = {
     description = "Python34 program that implements a command line tool for accessing the Redfish API";
     homepage = "https://github.com/DMTF/Redfishtool";
diff --git a/pkgs/by-name/re/regexploit/package.nix b/pkgs/by-name/re/regexploit/package.nix
index 62576425b164..8e9ecc549f05 100644
--- a/pkgs/by-name/re/regexploit/package.nix
+++ b/pkgs/by-name/re/regexploit/package.nix
@@ -7,7 +7,7 @@
 python3.pkgs.buildPythonApplication rec {
   pname = "regexploit";
   version = "1.0.0";
-  format = "setuptools";
+  pyproject = true;
 
   disabled = python3.pythonOlder "3.8";
 
@@ -18,7 +18,11 @@ python3.pkgs.buildPythonApplication rec {
     sha256 = "0z3fghsyw0ll36in7ihc0qi3gy7mqi6cw1mi8m8c8xb1nlwpfr0y";
   };
 
-  propagatedBuildInputs = with python3.pkgs; [
+  build-system = with python3.pkgs; [
+    setuptools
+  ];
+
+  dependencies = with python3.pkgs; [
     pyyaml
   ];
 
diff --git a/pkgs/by-name/re/replacement/package.nix b/pkgs/by-name/re/replacement/package.nix
index 104ad16a2f2f..60443b2d2400 100644
--- a/pkgs/by-name/re/replacement/package.nix
+++ b/pkgs/by-name/re/replacement/package.nix
@@ -7,7 +7,7 @@
 python3Packages.buildPythonApplication rec {
   pname = "replacement";
   version = "0.4.4";
-  format = "setuptools";
+  pyproject = true;
 
   disabled = python3Packages.isPy27;
 
@@ -18,7 +18,11 @@ python3Packages.buildPythonApplication rec {
     sha256 = "0j4lvn3rx1kqvxcsd8nhc2lgk48jyyl7qffhlkvakhy60f9lymj3";
   };
 
-  propagatedBuildInputs = with python3Packages; [
+  build-system = with python3Packages; [
+    setuptools
+  ];
+
+  dependencies = with python3Packages; [
     ruamel-yaml
   ];
 
diff --git a/pkgs/by-name/rf/rfc-bibtex/package.nix b/pkgs/by-name/rf/rfc-bibtex/package.nix
index e594574388bc..3ca11ac923cf 100644
--- a/pkgs/by-name/rf/rfc-bibtex/package.nix
+++ b/pkgs/by-name/rf/rfc-bibtex/package.nix
@@ -4,11 +4,10 @@
   python3,
 }:
 
-with python3.pkgs;
-buildPythonApplication rec {
+python3.pkgs.buildPythonApplication rec {
   pname = "rfc-bibtex";
   version = "0.3.2";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "iluxonchik";
@@ -17,7 +16,9 @@ buildPythonApplication rec {
     hash = "sha256-bPCNQqiG50vWVFA6J2kyxftwsXunHTNBdSkoIRYkb0s=";
   };
 
-  nativeCheckInputs = [
+  build-system = with python3.pkgs; [ setuptools ];
+
+  nativeCheckInputs = with python3.pkgs; [
     pytestCheckHook
     vcrpy
   ];
diff --git a/pkgs/by-name/ri/ripe-atlas-tools/package.nix b/pkgs/by-name/ri/ripe-atlas-tools/package.nix
index 196b7983e2aa..180750393089 100644
--- a/pkgs/by-name/ri/ripe-atlas-tools/package.nix
+++ b/pkgs/by-name/ri/ripe-atlas-tools/package.nix
@@ -8,7 +8,7 @@
 python3.pkgs.buildPythonApplication rec {
   pname = "ripe-atlas-tools";
   version = "3.1.0";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "RIPE-NCC";
@@ -24,13 +24,17 @@ python3.pkgs.buildPythonApplication rec {
     echo "include ripe/atlas/tools/user-agent" >> MANIFEST.in
   '';
 
-  nativeBuildInputs = with python3.pkgs; [
-    sphinx-rtd-theme
-    sphinxHook
+  nativeBuildInputs = [
     installShellFiles
   ];
 
-  propagatedBuildInputs = with python3.pkgs; [
+  build-system = with python3.pkgs; [
+    setuptools
+    sphinx-rtd-theme
+    sphinxHook
+  ];
+
+  dependencies = with python3.pkgs; [
     ipy
     pyopenssl
     python-dateutil
diff --git a/pkgs/by-name/ri/rivalcfg/package.nix b/pkgs/by-name/ri/rivalcfg/package.nix
index 669883f0a83b..7618d7e3a65e 100644
--- a/pkgs/by-name/ri/rivalcfg/package.nix
+++ b/pkgs/by-name/ri/rivalcfg/package.nix
@@ -7,7 +7,7 @@
 python3Packages.buildPythonPackage rec {
   pname = "rivalcfg";
   version = "4.15.0";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "flozz";
@@ -16,29 +16,33 @@ python3Packages.buildPythonPackage rec {
     sha256 = "sha256-UqVogJLv+sNhAxdMjBEvhBQw6LU+QUq1IekvWpeeMqk=";
   };
 
-  propagatedBuildInputs = with python3Packages; [
+  build-system = with python3Packages; [ setuptools ];
+
+  dependencies = with python3Packages; [
     hidapi
-    setuptools
+    setuptools # pkg_resources is imported during runtime
   ];
 
-  checkInputs = [ python3Packages.pytest ];
-  checkPhase = "pytest";
+  nativeCheckInputs = with python3Packages; [
+    pytestCheckHook
+  ];
 
   # tests are broken
   doCheck = false;
 
   postInstall = ''
-    set -x
     mkdir -p $out/lib/udev/rules.d
     tmpl_udev="$out/lib/udev/rules.d/99-rivalcfg.rules"
     tmpudev="''${tmpl_udev}.in"
     finaludev="$tmpl_udev"
     "$out/bin/rivalcfg" --print-udev > "$tmpudev"
     substitute "$tmpudev" "$out/lib/udev/rules.d/99-rivalcfg.rules" \
-      --replace MODE=\"0666\" "MODE=\"0664\", GROUP=\"input\""
+      --replace-fail MODE=\"0666\" "MODE=\"0664\", GROUP=\"input\""
     rm "$tmpudev"
   '';
 
+  pythonImportsCheck = [ "rivalcfg" ];
+
   meta = with lib; {
     description = "Utility program that allows you to configure SteelSeries Rival gaming mice";
     homepage = "https://github.com/flozz/rivalcfg";
diff --git a/pkgs/by-name/ro/rofi-mpd/package.nix b/pkgs/by-name/ro/rofi-mpd/package.nix
index 806b6a2169d4..7fa82ef3b53a 100644
--- a/pkgs/by-name/ro/rofi-mpd/package.nix
+++ b/pkgs/by-name/ro/rofi-mpd/package.nix
@@ -7,7 +7,7 @@
 python3Packages.buildPythonApplication rec {
   pname = "rofi-mpd";
   version = "2.2.1";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "JakeStanger";
@@ -16,7 +16,9 @@ python3Packages.buildPythonApplication rec {
     sha256 = "0jabyn6gqh8ychn2a06xws3avz0lqdnx3qvqkavfd2xr6sp2q7lg";
   };
 
-  propagatedBuildInputs = with python3Packages; [
+  build-system = with python3Packages; [ setuptools ];
+
+  dependencies = with python3Packages; [
     mutagen
     mpd2
     toml
diff --git a/pkgs/by-name/s3/s3bro/package.nix b/pkgs/by-name/s3/s3bro/package.nix
index fb5b8e8237e6..f8d5caff902e 100644
--- a/pkgs/by-name/s3/s3bro/package.nix
+++ b/pkgs/by-name/s3/s3bro/package.nix
@@ -7,14 +7,16 @@
 python3.pkgs.buildPythonApplication rec {
   pname = "s3bro";
   version = "2.8";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchPypi {
     inherit pname version;
     hash = "sha256-+OqcLbXilbY4h/zRAkvRd8taVIOPyiScOAcDyPZ4RUw=";
   };
 
-  propagatedBuildInputs = with python3.pkgs; [
+  build-system = with python3.pkgs; [ setuptools ];
+
+  dependencies = with python3.pkgs; [
     boto3
     botocore
     click
@@ -23,7 +25,7 @@ python3.pkgs.buildPythonApplication rec {
 
   postPatch = ''
     substituteInPlace setup.py \
-      --replace "use_2to3=True," ""
+      --replace-fail "use_2to3=True," ""
   '';
 
   # No tests
diff --git a/pkgs/by-name/s4/s4cmd/package.nix b/pkgs/by-name/s4/s4cmd/package.nix
index 2c2cf486757f..ef5ff67afc13 100644
--- a/pkgs/by-name/s4/s4cmd/package.nix
+++ b/pkgs/by-name/s4/s4cmd/package.nix
@@ -7,14 +7,16 @@
 python3Packages.buildPythonApplication rec {
   pname = "s4cmd";
   version = "2.1.0";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchPypi {
     inherit pname version;
     sha256 = "0d4mx98i3qhvlmr9x898mjvf827smzx6x5ji6daiwgjdlxc60mj2";
   };
 
-  propagatedBuildInputs = with python3Packages; [
+  build-system = with python3Packages; [ setuptools ];
+
+  dependencies = with python3Packages; [
     boto3
     pytz
   ];
@@ -34,6 +36,8 @@ python3Packages.buildPythonApplication rec {
   # Test suite requires an S3 bucket
   doCheck = false;
 
+  pythonImportsCheck = [ "s4cmd" ];
+
   meta = with lib; {
     homepage = "https://github.com/bloomreach/s4cmd";
     description = "Super S3 command line tool";
diff --git a/pkgs/by-name/sa/safeeyes/package.nix b/pkgs/by-name/sa/safeeyes/package.nix
index 5e87488b9fb2..dcce05e55338 100644
--- a/pkgs/by-name/sa/safeeyes/package.nix
+++ b/pkgs/by-name/sa/safeeyes/package.nix
@@ -14,12 +14,10 @@
   wrapGAppsHook3,
 }:
 
-with python3.pkgs;
-
-buildPythonApplication rec {
+python3.pkgs.buildPythonApplication rec {
   pname = "safeeyes";
   version = "2.2.3";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchPypi {
     inherit pname version;
@@ -27,7 +25,7 @@ buildPythonApplication rec {
   };
 
   postPatch = ''
-    substituteInPlace setup.py --replace "root_dir = sys.prefix" "root_dir = '/'"
+    substituteInPlace setup.py --replace-fail "root_dir = sys.prefix" "root_dir = '/'"
   '';
 
   nativeBuildInputs = [
@@ -40,14 +38,15 @@ buildPythonApplication rec {
     libnotify
   ];
 
-  propagatedBuildInputs = [
+  build-system = with python3.pkgs; [ setuptools ];
+
+  dependencies = with python3.pkgs; [
     babel
     psutil
     xlib
     pygobject3
     dbus-python
     croniter
-    setuptools
     packaging
   ];
 
@@ -74,6 +73,8 @@ buildPythonApplication rec {
 
   doCheck = false; # no tests
 
+  pythonImportsCheck = [ "safeeyes" ];
+
   passthru.tests.version = testers.testVersion { package = safeeyes; };
 
   meta = with lib; {
diff --git a/pkgs/by-name/sa/savepagenow/package.nix b/pkgs/by-name/sa/savepagenow/package.nix
index 5875b96cce19..4be414d2f8c2 100644
--- a/pkgs/by-name/sa/savepagenow/package.nix
+++ b/pkgs/by-name/sa/savepagenow/package.nix
@@ -7,7 +7,7 @@
 python3Packages.buildPythonApplication rec {
   pname = "savepagenow";
   version = "1.1.1";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "pastpages";
@@ -16,7 +16,9 @@ python3Packages.buildPythonApplication rec {
     sha256 = "1lz6rc47cds9rb35jdf8n13gr61wdkh5jqzx4skikm1yrqkwjyhm";
   };
 
-  propagatedBuildInputs = with python3Packages; [
+  build-system = with python3Packages; [ setuptools ];
+
+  dependencies = with python3Packages; [
     click
     requests
   ];
@@ -24,6 +26,8 @@ python3Packages.buildPythonApplication rec {
   # requires network access
   doCheck = false;
 
+  pythonImportsCheck = [ "savepagenow" ];
+
   meta = with lib; {
     description = "Simple Python wrapper for archive.org's \"Save Page Now\" capturing service";
     homepage = "https://github.com/pastpages/savepagenow";
diff --git a/pkgs/by-name/sc/sca2d/package.nix b/pkgs/by-name/sc/sca2d/package.nix
index 4cca153e6f95..f18a765769c2 100644
--- a/pkgs/by-name/sc/sca2d/package.nix
+++ b/pkgs/by-name/sc/sca2d/package.nix
@@ -28,7 +28,7 @@ in
 python.pkgs.buildPythonApplication rec {
   pname = "sca2d";
   version = "0.2.2";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitLab {
     owner = "bath_open_instrumentation_group";
@@ -37,7 +37,9 @@ python.pkgs.buildPythonApplication rec {
     hash = "sha256-p0Bv8jcnjcOLBAXN5A4GspSIEG4G4NPA4o0aEtwe/LU=";
   };
 
-  propagatedBuildInputs = with python.pkgs; [
+  build-system = with python.pkgs; [ setuptools ];
+
+  dependencies = with python.pkgs; [
     lark010
     colorama
   ];
diff --git a/pkgs/by-name/sc/screenkey/package.nix b/pkgs/by-name/sc/screenkey/package.nix
index c5b02d2d8cc0..7a6a15c732b5 100644
--- a/pkgs/by-name/sc/screenkey/package.nix
+++ b/pkgs/by-name/sc/screenkey/package.nix
@@ -13,7 +13,7 @@
 python3.pkgs.buildPythonApplication rec {
   pname = "screenkey";
   version = "1.5";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitLab {
     owner = "screenkey";
@@ -33,7 +33,9 @@ python3.pkgs.buildPythonApplication rec {
     libappindicator-gtk3
   ];
 
-  propagatedBuildInputs = with python3.pkgs; [
+  build-system = with python3.pkgs; [ setuptools ];
+
+  dependencies = with python3.pkgs; [
     babel
     pycairo
     pygobject3
@@ -53,11 +55,13 @@ python3.pkgs.buildPythonApplication rec {
   # screenkey does not have any tests
   doCheck = false;
 
+  pythonImportsCheck = [ "Screenkey" ];
+
   # Fix CDLL python calls for non absolute paths of xorg libraries
   postPatch = ''
     substituteInPlace Screenkey/xlib.py \
-      --replace libX11.so.6 ${lib.getLib xorg.libX11}/lib/libX11.so.6 \
-      --replace libXtst.so.6 ${lib.getLib xorg.libXtst}/lib/libXtst.so.6
+      --replace-fail libX11.so.6 ${lib.getLib xorg.libX11}/lib/libX11.so.6 \
+      --replace-fail libXtst.so.6 ${lib.getLib xorg.libXtst}/lib/libXtst.so.6
   '';
 
   meta = with lib; {
diff --git a/pkgs/by-name/se/seashells/package.nix b/pkgs/by-name/se/seashells/package.nix
index c190a458fbce..d4c6e663166a 100644
--- a/pkgs/by-name/se/seashells/package.nix
+++ b/pkgs/by-name/se/seashells/package.nix
@@ -7,13 +7,15 @@
 python3Packages.buildPythonApplication rec {
   pname = "seashells";
   version = "0.1.2";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchPypi {
     inherit pname version;
     hash = "sha256-RBs28FC7f82DrxRcmvTP9nljVpm7tjrGuvr05l32hDM=";
   };
 
+  build-system = with python3Packages; [ setuptools ];
+
   doCheck = false; # there are no tests
   pythonImportsCheck = [ "seashells" ];
 
diff --git a/pkgs/by-name/se/semiphemeral/package.nix b/pkgs/by-name/se/semiphemeral/package.nix
index 2cc721a2228b..90f419d35432 100644
--- a/pkgs/by-name/se/semiphemeral/package.nix
+++ b/pkgs/by-name/se/semiphemeral/package.nix
@@ -7,7 +7,7 @@
 python3.pkgs.buildPythonApplication rec {
   pname = "semiphemeral";
   version = "0.7";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchPypi {
     inherit pname version;
@@ -18,7 +18,9 @@ python3.pkgs.buildPythonApplication rec {
 
   pythonImportsCheck = [ "semiphemeral" ];
 
-  propagatedBuildInputs = with python3.pkgs; [
+  build-system = with python3.pkgs; [ setuptools ];
+
+  dependencies = with python3.pkgs; [
     click
     sqlalchemy
     flask
diff --git a/pkgs/by-name/se/seventeenlands/package.nix b/pkgs/by-name/se/seventeenlands/package.nix
index 649a5280e464..0691a82035ee 100644
--- a/pkgs/by-name/se/seventeenlands/package.nix
+++ b/pkgs/by-name/se/seventeenlands/package.nix
@@ -6,7 +6,7 @@
 python3.pkgs.buildPythonApplication rec {
   pname = "seventeenlands";
   version = "0.1.43";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchPypi {
     inherit pname version;
@@ -18,7 +18,9 @@ python3.pkgs.buildPythonApplication rec {
 
   pythonImportsCheck = [ "seventeenlands" ];
 
-  propagatedBuildInputs = with python3.pkgs; [
+  build-system = with python3.pkgs; [ setuptools ];
+
+  dependencies = with python3.pkgs; [
     python-dateutil
     requests
     tkinter
diff --git a/pkgs/by-name/se/sewer/package.nix b/pkgs/by-name/se/sewer/package.nix
index 17049eb5db10..d2a6240f48fe 100644
--- a/pkgs/by-name/se/sewer/package.nix
+++ b/pkgs/by-name/se/sewer/package.nix
@@ -7,19 +7,23 @@
 python3Packages.buildPythonApplication rec {
   pname = "sewer";
   version = "0.8.4";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchPypi {
     inherit pname version;
     sha256 = "sha256-a4VdbZY8pYxrXIaUHJpnLuTB928tJn4UCdnt+m8UBug=";
   };
 
-  propagatedBuildInputs = with python3Packages; [
+  build-system = with python3Packages; [ setuptools ];
+
+  dependencies = with python3Packages; [
     pyopenssl
     requests
     tldextract
   ];
 
+  pythonImportsCheck = [ "sewer" ];
+
   meta = with lib; {
     homepage = "https://github.com/komuw/sewer";
     description = "ACME client";
diff --git a/pkgs/by-name/sf/sftpman/package.nix b/pkgs/by-name/sf/sftpman/package.nix
index 26ea3d4b7e40..db9b5143c296 100644
--- a/pkgs/by-name/sf/sftpman/package.nix
+++ b/pkgs/by-name/sf/sftpman/package.nix
@@ -7,7 +7,7 @@
 python3Packages.buildPythonApplication rec {
   pname = "sftpman";
   version = "1.2.2";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "spantaleev";
@@ -16,10 +16,14 @@ python3Packages.buildPythonApplication rec {
     hash = "sha256-YxqN4+u0nYUWehbyRhjddIo2sythH3E0fiPSyrUlWhM=";
   };
 
+  build-system = with python3Packages; [ setuptools ];
+
   checkPhase = ''
     $out/bin/sftpman help
   '';
 
+  pythonImportsCheck = [ "sftpman" ];
+
   meta = with lib; {
     homepage = "https://github.com/spantaleev/sftpman";
     description = "Application that handles sshfs/sftp file systems mounting";
diff --git a/pkgs/by-name/sh/shot-scraper/package.nix b/pkgs/by-name/sh/shot-scraper/package.nix
index 86a921b1042b..5f3ff70cf52f 100644
--- a/pkgs/by-name/sh/shot-scraper/package.nix
+++ b/pkgs/by-name/sh/shot-scraper/package.nix
@@ -7,7 +7,7 @@
 python3.pkgs.buildPythonApplication rec {
   pname = "shot-scraper";
   version = "1.8";
-  format = "setuptools";
+  pyproject = true;
 
   disabled = python3.pkgs.pythonOlder "3.6";
 
@@ -18,7 +18,9 @@ python3.pkgs.buildPythonApplication rec {
     hash = "sha256-CSV9HOqVMHI/L+jyMTdaDyc6ACyGIkG/mmcyRza6EjQ=";
   };
 
-  propagatedBuildInputs = with python3.pkgs; [
+  build-system = with python3.pkgs; [ setuptools ];
+
+  dependencies = with python3.pkgs; [
     click
     click-default-group
     playwright
diff --git a/pkgs/by-name/so/soco-cli/package.nix b/pkgs/by-name/so/soco-cli/package.nix
index edf5ffc461fe..434b6a2dd167 100644
--- a/pkgs/by-name/so/soco-cli/package.nix
+++ b/pkgs/by-name/so/soco-cli/package.nix
@@ -7,7 +7,7 @@
 python3.pkgs.buildPythonApplication rec {
   pname = "soco-cli";
   version = "0.4.73";
-  format = "setuptools";
+  pyproject = true;
 
   disabled = python3.pythonOlder "3.6";
 
@@ -18,7 +18,9 @@ python3.pkgs.buildPythonApplication rec {
     hash = "sha256-WxBwHjh5tCXclQXqrHrpvZdcQU93RObteAfZyyVvKf0=";
   };
 
-  propagatedBuildInputs = with python3.pkgs; [
+  build-system = with python3.pkgs; [ setuptools ];
+
+  dependencies = with python3.pkgs; [
     fastapi
     rangehttpserver
     soco
diff --git a/pkgs/by-name/so/sonata/package.nix b/pkgs/by-name/so/sonata/package.nix
index 46e2504fae87..0e2f2ca7d74c 100644
--- a/pkgs/by-name/so/sonata/package.nix
+++ b/pkgs/by-name/so/sonata/package.nix
@@ -25,7 +25,7 @@ in
 buildPythonApplication rec {
   pname = "sonata";
   version = "1.7.1";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "multani";
@@ -50,13 +50,15 @@ buildPythonApplication rec {
     gdk-pixbuf
   ];
 
+  build-system = [ setuptools ];
+
   # The optional tagpy dependency (for editing metadata) is not yet
   # included because it's difficult to build.
   pythonPath = [
     dbus-python
     mpd2
     pygobject3
-    setuptools
+    setuptools # pkg_resources is imported during runtime
   ];
 
   postPatch = ''
diff --git a/pkgs/by-name/sq/sqlite-web/package.nix b/pkgs/by-name/sq/sqlite-web/package.nix
index 6dea15352a99..b1128260999b 100644
--- a/pkgs/by-name/sq/sqlite-web/package.nix
+++ b/pkgs/by-name/sq/sqlite-web/package.nix
@@ -7,14 +7,16 @@
 python3Packages.buildPythonApplication rec {
   pname = "sqlite-web";
   version = "0.6.4";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchPypi {
     inherit pname version;
     hash = "sha256-5Bdd1C9M3HjvfDKdVvGSQ+/I0Iimvf1MZwPonRiqwqU=";
   };
 
-  propagatedBuildInputs = with python3Packages; [
+  build-system = with python3Packages; [ setuptools ];
+
+  dependencies = with python3Packages; [
     flask
     peewee
     pygments
@@ -23,6 +25,8 @@ python3Packages.buildPythonApplication rec {
   # no tests in repository
   doCheck = false;
 
+  pythonImportsCheck = [ "sqlite_web" ];
+
   meta = with lib; {
     description = "Web-based SQLite database browser";
     mainProgram = "sqlite_web";
diff --git a/pkgs/by-name/sw/swaggerhole/package.nix b/pkgs/by-name/sw/swaggerhole/package.nix
index d1311c61fd8f..a6d6868ff1c0 100644
--- a/pkgs/by-name/sw/swaggerhole/package.nix
+++ b/pkgs/by-name/sw/swaggerhole/package.nix
@@ -7,7 +7,7 @@
 python3.pkgs.buildPythonApplication {
   pname = "swaggerhole";
   version = "1.1";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "Liodeus";
@@ -17,7 +17,9 @@ python3.pkgs.buildPythonApplication {
     hash = "sha256-3HmIpn1A86PXZRL+SqMdr84O16hW1mCUWHKnOVolmx8=";
   };
 
-  propagatedBuildInputs = with python3.pkgs; [
+  build-system = with python3.pkgs; [ setuptools ];
+
+  dependencies = with python3.pkgs; [
     requests
     whispers
   ];
diff --git a/pkgs/by-name/sw/swaglyrics/package.nix b/pkgs/by-name/sw/swaglyrics/package.nix
index b2e567afc5cf..5c4e6031286b 100644
--- a/pkgs/by-name/sw/swaglyrics/package.nix
+++ b/pkgs/by-name/sw/swaglyrics/package.nix
@@ -8,7 +8,7 @@
 python3.pkgs.buildPythonApplication {
   pname = "swaglyrics";
   version = "unstable-2021-06-17";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "SwagLyrics";
@@ -19,10 +19,12 @@ python3.pkgs.buildPythonApplication {
 
   postPatch = ''
     substituteInPlace setup.py \
-      --replace "==" ">="
+      --replace-fail "==" ">="
   '';
 
-  propagatedBuildInputs = with python3.pkgs; [
+  build-system = with python3.pkgs; [ setuptools ];
+
+  dependencies = with python3.pkgs; [
     beautifulsoup4
     colorama
     flask
diff --git a/pkgs/by-name/sy/syncrclone/package.nix b/pkgs/by-name/sy/syncrclone/package.nix
index d5fd5968f0e9..a23ae28d8e71 100644
--- a/pkgs/by-name/sy/syncrclone/package.nix
+++ b/pkgs/by-name/sy/syncrclone/package.nix
@@ -7,7 +7,7 @@
 python3.pkgs.buildPythonApplication rec {
   pname = "syncrclone";
   version = "unstable-2023-03-23";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "jwink3101";
@@ -16,6 +16,8 @@ python3.pkgs.buildPythonApplication rec {
     hash = "sha256-v81hPeu5qnMG6Sb95D88jy5x/GO781bf7efCYjbOaxs=";
   };
 
+  build-system = with python3.pkgs; [ setuptools ];
+
   pythonImportsCheck = [
     "syncrclone"
   ];
diff --git a/pkgs/by-name/sy/systemd-wait/package.nix b/pkgs/by-name/sy/systemd-wait/package.nix
index d5e054ccb14b..a19db9b7acf5 100644
--- a/pkgs/by-name/sy/systemd-wait/package.nix
+++ b/pkgs/by-name/sy/systemd-wait/package.nix
@@ -7,7 +7,7 @@
 python3Packages.buildPythonApplication {
   pname = "systemd-wait";
   version = "0.1+2018-10-05";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "Stebalien";
@@ -16,7 +16,9 @@ python3Packages.buildPythonApplication {
     sha256 = "1l8rd0wzf3m7fk0g1c8wc0csdisdfac0filhixpgp0ck9ignayq5";
   };
 
-  propagatedBuildInputs = with python3Packages; [
+  build-system = with python3Packages; [ setuptools ];
+
+  dependencies = with python3Packages; [
     dbus-python
     pygobject3
   ];
diff --git a/pkgs/by-name/ta/tauon/package.nix b/pkgs/by-name/ta/tauon/package.nix
index b4c8ac5cbac5..d302aa1650b2 100644
--- a/pkgs/by-name/ta/tauon/package.nix
+++ b/pkgs/by-name/ta/tauon/package.nix
@@ -33,13 +33,15 @@ let
   lynxpresence = python3Packages.buildPythonPackage rec {
     pname = "lynxpresence";
     version = "4.4.1";
-    format = "setuptools";
+    pyproject = true;
 
     src = fetchPypi {
       inherit pname version;
       hash = "sha256-y/KboyhEGs9RvyKayEIQu2+WaiQNOdsHDl1/pEoqEkQ=";
     };
 
+    build-system = with python3Packages; [ setuptools ];
+
     doCheck = false; # tests require internet connection
     pythonImportsCheck = [ "lynxpresence" ];
   };
diff --git a/pkgs/by-name/te/tebreak/package.nix b/pkgs/by-name/te/tebreak/package.nix
index 40ad4527916e..1a8107b35310 100644
--- a/pkgs/by-name/te/tebreak/package.nix
+++ b/pkgs/by-name/te/tebreak/package.nix
@@ -12,7 +12,7 @@
 python3.pkgs.buildPythonApplication rec {
   pname = "tebreak";
   version = "1.1";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "adamewing";
@@ -21,8 +21,9 @@ python3.pkgs.buildPythonApplication rec {
     sha256 = "13mgh775d8hkl340923lfwwm4r5ps70girn8d6wgfxzwzxylz8iz";
   };
 
-  nativeBuildInputs = [ python3.pkgs.cython ];
-  propagatedBuildInputs = with python3.pkgs; [
+  build-system = with python3.pkgs; [ setuptools ];
+
+  dependencies = with python3.pkgs; [
     pysam
     scipy
     bx-python
@@ -47,6 +48,8 @@ python3.pkgs.buildPythonApplication rec {
     ${python3.interpreter} checktest.py
   '';
 
+  pythonImportsCheck = [ "tebreak" ];
+
   meta = with lib; {
     description = "Find and characterise transposable element insertions";
     mainProgram = "tebreak";
diff --git a/pkgs/by-name/te/terminator/package.nix b/pkgs/by-name/te/terminator/package.nix
index 80ca31f6ccc6..22c84eb5d36e 100644
--- a/pkgs/by-name/te/terminator/package.nix
+++ b/pkgs/by-name/te/terminator/package.nix
@@ -17,7 +17,7 @@
 python3.pkgs.buildPythonApplication rec {
   pname = "terminator";
   version = "2.1.5";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "gnome-terminator";
@@ -42,7 +42,9 @@ python3.pkgs.buildPythonApplication rec {
     vte
   ];
 
-  propagatedBuildInputs = with python3.pkgs; [
+  build-system = with python3.pkgs; [ setuptools ];
+
+  dependencies = with python3.pkgs; [
     configobj
     dbus-python
     pygobject3
@@ -56,6 +58,8 @@ python3.pkgs.buildPythonApplication rec {
 
   doCheck = false;
 
+  pythonImportsCheck = [ "terminatorlib" ];
+
   dontWrapGApps = true;
 
   # HACK: 'wrapPythonPrograms' will add things to the $PATH in the wrapper. This bleeds into the
diff --git a/pkgs/by-name/te/termtosvg/package.nix b/pkgs/by-name/te/termtosvg/package.nix
index 038168c53a56..5b30ecef9a4e 100644
--- a/pkgs/by-name/te/termtosvg/package.nix
+++ b/pkgs/by-name/te/termtosvg/package.nix
@@ -7,19 +7,23 @@
 python3Packages.buildPythonApplication rec {
   pname = "termtosvg";
   version = "1.1.0";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchPypi {
     inherit pname version;
     sha256 = "1vk5kn8w3zf2ymi76l8cpwmvvavkmh3b9lb18xw3x1vzbmhz2f7d";
   };
 
-  propagatedBuildInputs = with python3Packages; [
+  build-system = with python3Packages; [ setuptools ];
+
+  dependencies = with python3Packages; [
     lxml
     pyte
     wcwidth
   ];
 
+  pythonImportsCheck = [ "termtosvg" ];
+
   meta = with lib; {
     homepage = "https://nbedos.github.io/termtosvg/";
     description = "Record terminal sessions as SVG animations";
diff --git a/pkgs/by-name/te/terraform-compliance/package.nix b/pkgs/by-name/te/terraform-compliance/package.nix
index 2edb96777f3b..0ab9c03badb4 100644
--- a/pkgs/by-name/te/terraform-compliance/package.nix
+++ b/pkgs/by-name/te/terraform-compliance/package.nix
@@ -7,7 +7,7 @@
 python3.pkgs.buildPythonApplication rec {
   pname = "terraform-compliance";
   version = "1.3.52";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "terraform-compliance";
@@ -16,14 +16,14 @@ python3.pkgs.buildPythonApplication rec {
     hash = "sha256-M6u1P1UxOrP9bNPjPB0V15DUj+Y/1dFIjf/GCnYoCwc=";
   };
 
-  postPatch = ''
-    substituteInPlace setup.py \
-      --replace "IPython==7.16.1" "IPython" \
-      --replace "diskcache==5.1.0" "diskcache>=5.1.0" \
-      --replace "radish-bdd==0.13.1" "radish-bdd" \
-  '';
+  build-system = with python3.pkgs; [ setuptools ];
 
-  propagatedBuildInputs = with python3.pkgs; [
+  pythonRelaxDeps = [
+    "radish-bdd"
+    "IPython"
+  ];
+
+  dependencies = with python3.pkgs; [
     diskcache
     emoji
     filetype
diff --git a/pkgs/by-name/th/thonny/package.nix b/pkgs/by-name/th/thonny/package.nix
index c99854b9adaa..0a8b0cc8b0d9 100644
--- a/pkgs/by-name/th/thonny/package.nix
+++ b/pkgs/by-name/th/thonny/package.nix
@@ -8,12 +8,10 @@
   desktopToDarwinBundle,
 }:
 
-with python3.pkgs;
-
-buildPythonApplication rec {
+python3.pkgs.buildPythonApplication rec {
   pname = "thonny";
   version = "4.1.7";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "thonny";
@@ -40,6 +38,8 @@ buildPythonApplication rec {
     })
   ];
 
+  build-system = with python3.pkgs; [ setuptools ];
+
   dependencies =
     with python3.pkgs;
     (
@@ -71,6 +71,8 @@ buildPythonApplication rec {
   # Tests need a DISPLAY
   doCheck = false;
 
+  pythonImportsCheck = [ "thonny" ];
+
   meta = {
     description = "Python IDE for beginners";
     longDescription = ''
diff --git a/pkgs/by-name/ti/timetagger_cli/package.nix b/pkgs/by-name/ti/timetagger_cli/package.nix
index 55cd89448477..a3edce502af7 100644
--- a/pkgs/by-name/ti/timetagger_cli/package.nix
+++ b/pkgs/by-name/ti/timetagger_cli/package.nix
@@ -7,7 +7,7 @@
 python3.pkgs.buildPythonApplication rec {
   pname = "timetagger_cli";
   version = "25.5.1";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "almarklein";
@@ -16,14 +16,19 @@ python3.pkgs.buildPythonApplication rec {
     hash = "sha256-UklsHcVyCpWDHOxu+oB8RvwY+laEBFnDyjejS/GzgHE=";
   };
 
-  propagatedBuildInputs = with python3.pkgs; [
+  build-system = with python3.pkgs; [ setuptools ];
+
+  dependencies = with python3.pkgs; [
     requests
     toml
+    dateparser
   ];
 
   # Project has no tests
   doCheck = false;
 
+  pythonImportsCheck = [ "timetagger_cli" ];
+
   meta = with lib; {
     description = "Track your time from the command-line";
     homepage = "https://github.com/almarklein/timetagger_cli";
diff --git a/pkgs/by-name/ti/tinyprog/package.nix b/pkgs/by-name/ti/tinyprog/package.nix
index a57d25473b6f..a0d7cf880a40 100644
--- a/pkgs/by-name/ti/tinyprog/package.nix
+++ b/pkgs/by-name/ti/tinyprog/package.nix
@@ -9,7 +9,7 @@ buildPythonApplication rec {
   pname = "tinyprog";
   # `python setup.py --version` from repo checkout
   version = "1.0.24.dev114+g${lib.substring 0 7 src.rev}";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "tinyfpga";
@@ -20,19 +20,22 @@ buildPythonApplication rec {
 
   sourceRoot = "${src.name}/programmer";
 
-  propagatedBuildInputs = [
+  build-system = with python3Packages; [
+    setuptools
+    setuptools-scm
+  ];
+
+  dependencies = [
     pyserial
     jsonmerge
     intelhex
     tqdm
     six
     packaging
-    setuptools
+    setuptools # pkg_resources is imported during runtime
     pyusb
   ];
 
-  nativeBuildInputs = [ setuptools-scm ];
-
   meta = with lib; {
     homepage = "https://github.com/tinyfpga/TinyFPGA-Bootloader/tree/master/programmer";
     description = "Programmer for FPGA boards using the TinyFPGA USB Bootloader";
diff --git a/pkgs/by-name/to/tockloader/package.nix b/pkgs/by-name/to/tockloader/package.nix
index 5f8f6f710bae..32b6181c6f57 100644
--- a/pkgs/by-name/to/tockloader/package.nix
+++ b/pkgs/by-name/to/tockloader/package.nix
@@ -7,14 +7,16 @@
 python3.pkgs.buildPythonApplication rec {
   pname = "tockloader";
   version = "1.9.0";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchPypi {
     inherit pname version;
     hash = "sha256-7W55jugVtamFUL8N3dD1LFLJP2UDQb74V6o96rd/tEg=";
   };
 
-  propagatedBuildInputs = with python3.pkgs; [
+  build-system = with python3.pkgs; [ setuptools ];
+
+  dependencies = with python3.pkgs; [
     argcomplete
     colorama
     crcmod
@@ -32,6 +34,8 @@ python3.pkgs.buildPythonApplication rec {
     runHook postCheck
   '';
 
+  pythonImportsCheck = [ "tockloader" ];
+
   meta = {
     description = "Tool for programming Tock onto hardware boards";
     mainProgram = "tockloader";
diff --git a/pkgs/by-name/tr/trash-cli/package.nix b/pkgs/by-name/tr/trash-cli/package.nix
index b86a434cb10c..b645d5a3ec78 100644
--- a/pkgs/by-name/tr/trash-cli/package.nix
+++ b/pkgs/by-name/tr/trash-cli/package.nix
@@ -9,7 +9,7 @@
 python3Packages.buildPythonApplication rec {
   pname = "trash-cli";
   version = "0.24.5.26";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "andreafrancia";
@@ -18,14 +18,18 @@ python3Packages.buildPythonApplication rec {
     hash = "sha256-ltuMnxtG4jTTSZd6ZHWl8wI0oQMMFqW0HAPetZMfGtc=";
   };
 
-  propagatedBuildInputs = with python3Packages; [
-    psutil
-    six
+  nativeBuildInputs = [
+    installShellFiles
   ];
 
-  nativeBuildInputs = with python3Packages; [
-    installShellFiles
-    shtab
+  build-system = with python3Packages; [
+    setuptools
+    shtab # for shell completions
+  ];
+
+  dependencies = with python3Packages; [
+    psutil
+    six
   ];
 
   nativeCheckInputs = with python3Packages; [
@@ -58,6 +62,9 @@ python3Packages.buildPythonApplication rec {
 
     runHook postInstallCheck
   '';
+
+  pythonImportsCheck = [ "trashcli" ];
+
   postInstall = ''
     for bin in trash-empty trash-list trash-restore trash-put trash; do
       installShellCompletion --cmd "$bin" \
diff --git a/pkgs/by-name/tu/tuir/package.nix b/pkgs/by-name/tu/tuir/package.nix
index 7570298cb6c8..638d639a9e38 100644
--- a/pkgs/by-name/tu/tuir/package.nix
+++ b/pkgs/by-name/tu/tuir/package.nix
@@ -8,7 +8,7 @@ with python3Packages;
 buildPythonApplication rec {
   pname = "tuir";
   version = "1.31.0";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitLab {
     owner = "Chocimier";
@@ -17,24 +17,9 @@ buildPythonApplication rec {
     hash = "sha256-VYBtD3Ex6+iIRNvX6jF0b0iPvno41/58xCRydiyssvk=";
   };
 
-  # Tests try to access network
-  doCheck = false;
+  build-system = with python3Packages; [ setuptools ];
 
-  checkPhase = ''
-    py.test
-  '';
-
-  nativeCheckInputs = [
-    coverage
-    coveralls
-    docopt
-    mock
-    pylint
-    pytest
-    vcrpy
-  ];
-
-  propagatedBuildInputs = [
+  dependencies = [
     beautifulsoup4
     decorator
     kitchen
@@ -43,6 +28,27 @@ buildPythonApplication rec {
     six
   ];
 
+  nativeCheckInputs = [
+    coverage
+    coveralls
+    docopt
+    mock
+    pylint
+    pytestCheckHook
+    vcrpy
+  ];
+
+  __darwinAllowLocalNetworking = true; # for oauth tests
+
+  disabledTests = lib.optionals stdenv.hostPlatform.isDarwin [
+    # AssertionError: assert ['pbcopy', 'w'] == ['xclip', '-s..., 'clipboard']
+    "test_copy_nix"
+    # AttributeError: Can't get local object 'Terminal.open_browser.open_browser.<locals>.open_url_silent'
+    "test_terminal_open_browser_display"
+  ];
+
+  pythonImportsCheck = [ "tuir" ];
+
   meta = with lib; {
     description = "Browse Reddit from your Terminal (fork of rtv)";
     mainProgram = "tuir";
diff --git a/pkgs/by-name/tv/tvnamer/package.nix b/pkgs/by-name/tv/tvnamer/package.nix
index 1141a473d643..c5e83e3ab788 100644
--- a/pkgs/by-name/tv/tvnamer/package.nix
+++ b/pkgs/by-name/tv/tvnamer/package.nix
@@ -34,18 +34,22 @@ in
 pypkgs.buildPythonApplication rec {
   pname = "tvnamer";
   version = "3.0.4";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchPypi {
     inherit pname version;
     sha256 = "dc2ea8188df6ac56439343630466b874c57756dd0b2538dd8e7905048f425f04";
   };
 
-  propagatedBuildInputs = with pypkgs; [ tvdb-api ];
+  build-system = with pypkgs; [ setuptools ];
+
+  dependencies = with pypkgs; [ tvdb-api ];
 
   # no tests from pypi
   doCheck = false;
 
+  pythonImportsCheck = [ "tvnamer" ];
+
   meta = with lib; {
     description = "Automatic TV episode file renamer, uses data from thetvdb.com via tvdb_api";
     homepage = "https://github.com/dbr/tvnamer";
diff --git a/pkgs/by-name/tx/txt2tags/package.nix b/pkgs/by-name/tx/txt2tags/package.nix
index 7f8a028cbd7d..59213b1913ea 100644
--- a/pkgs/by-name/tx/txt2tags/package.nix
+++ b/pkgs/by-name/tx/txt2tags/package.nix
@@ -8,7 +8,7 @@ python3.pkgs.buildPythonApplication rec {
   pname = "txt2tags";
   version = "3.9";
 
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "txt2tags";
@@ -17,17 +17,21 @@ python3.pkgs.buildPythonApplication rec {
     hash = "sha256-PwPGJJg79ny13gEb1WmgIVHcXQppI/j5mhIyOZjR19k=";
   };
 
+  build-system = with python3.pkgs; [ setuptools ];
+
   postPatch = ''
     substituteInPlace test/lib.py \
-      --replace 'TXT2TAGS = os.path.join(TEST_DIR, "..", "txt2tags.py")' \
-                'TXT2TAGS = "${placeholder "out"}/bin/txt2tags"' \
-      --replace "[PYTHON] + TXT2TAGS" "TXT2TAGS"
+      --replace-fail 'TXT2TAGS = os.path.join(TEST_DIR, "..", "txt2tags.py")' \
+                     'TXT2TAGS = "${placeholder "out"}/bin/txt2tags"' \
+      --replace-fail "[PYTHON] + TXT2TAGS" "TXT2TAGS"
   '';
 
   checkPhase = ''
     ${python3.interpreter} test/run.py
   '';
 
+  pythonImportsCheck = [ "txt2tags" ];
+
   meta = {
     changelog = "https://github.com/txt2tags/txt2tags/blob/${src.rev}/CHANGELOG.md";
     description = "Convert between markup languages";