diff --git a/pkgs/development/python-modules/easygui/default.nix b/pkgs/development/python-modules/easygui/default.nix
index e7d26d34492a..ffd99c3a4f33 100644
--- a/pkgs/development/python-modules/easygui/default.nix
+++ b/pkgs/development/python-modules/easygui/default.nix
@@ -2,13 +2,14 @@
   lib,
   fetchPypi,
   buildPythonPackage,
+  setuptools,
   tkinter,
 }:
 
 buildPythonPackage (finalAttrs: {
   pname = "easygui";
   version = "0.98.3";
-  format = "setuptools";
+  pyproject = true;
 
   __structuredAttrs = true;
 
@@ -17,7 +18,9 @@ buildPythonPackage (finalAttrs: {
     hash = "sha256-1lP/ee4fQvY7WgkPL5jOAjNdhq2JY7POJmGAXK/pmgQ=";
   };
 
-  propagatedBuildInputs = [ tkinter ];
+  build-system = [ setuptools ];
+
+  dependencies = [ tkinter ];
 
   doCheck = false; # No tests available