diff --git a/pkgs/development/python-modules/datefinder/default.nix b/pkgs/development/python-modules/datefinder/default.nix
index 953bd24bb409..e69eb68848fd 100644
--- a/pkgs/development/python-modules/datefinder/default.nix
+++ b/pkgs/development/python-modules/datefinder/default.nix
@@ -2,25 +2,30 @@
   lib,
   buildPythonPackage,
   fetchFromGitHub,
+  setuptools,
   pytestCheckHook,
   python-dateutil,
   pytz,
   regex,
 }:
 
-buildPythonPackage rec {
+buildPythonPackage (finalAttrs: {
   pname = "datefinder";
   version = "0.7.3";
-  format = "setuptools";
+  pyproject = true;
+
+  __structuredAttrs = true;
 
   src = fetchFromGitHub {
     owner = "akoumjian";
     repo = "datefinder";
-    tag = "v${version}";
+    tag = "v${finalAttrs.version}";
     hash = "sha256-uOSwS+mHgbvEL+rTfs4Ax9NvJnhYemxFVqqDssy2i7g=";
   };
 
-  propagatedBuildInputs = [
+  build-system = [ setuptools ];
+
+  dependencies = [
     regex
     pytz
     python-dateutil
@@ -39,4 +44,4 @@ buildPythonPackage rec {
       despsyched
     ];
   };
-}
+})