diff --git a/pkgs/development/python-modules/csscompressor/default.nix b/pkgs/development/python-modules/csscompressor/default.nix
index e6a1e5245633..b90bab5c3b4d 100644
--- a/pkgs/development/python-modules/csscompressor/default.nix
+++ b/pkgs/development/python-modules/csscompressor/default.nix
@@ -2,19 +2,23 @@
   lib,
   buildPythonPackage,
   fetchPypi,
+  pytestCheckHook,
+  setuptools,
 }:
 
-buildPythonPackage rec {
+buildPythonPackage (finalAttrs: {
   pname = "csscompressor";
   version = "0.9.5";
-  format = "setuptools";
+  pyproject = true;
 
   src = fetchPypi {
-    inherit pname version;
-    sha256 = "afa22badbcf3120a4f392e4d22f9fff485c044a1feda4a950ecc5eba9dd31a05";
+    inherit (finalAttrs) pname version;
+    hash = "sha256-r6IrrbzzEgpPOS5NIvn/9IXARKH+2kqVDsxeup3TGgU=";
   };
 
-  doCheck = false; # No tests
+  build-system = [ setuptools ];
+
+  nativeCheckInputs = [ pytestCheckHook ];
 
   meta = {
     description = "Python port of YUI CSS Compressor";
@@ -22,4 +26,4 @@ buildPythonPackage rec {
     license = lib.licenses.bsd3;
     maintainers = [ ];
   };
-}
+})