diff --git a/pkgs/development/python-modules/daff/default.nix b/pkgs/development/python-modules/daff/default.nix
index fe2cdb94db0d..239b46660a09 100644
--- a/pkgs/development/python-modules/daff/default.nix
+++ b/pkgs/development/python-modules/daff/default.nix
@@ -2,18 +2,23 @@
   lib,
   buildPythonPackage,
   fetchPypi,
+  setuptools,
 }:
 
-buildPythonPackage rec {
+buildPythonPackage (finalAttrs: {
   pname = "daff";
   version = "1.4.2";
-  format = "setuptools";
+  pyproject = true;
+
+  __structuredAttrs = true;
 
   src = fetchPypi {
-    inherit pname version;
+    inherit (finalAttrs) pname version;
     hash = "sha256-R/A5Htp+K1AR98ysAGuReKzLRlvLlKLJ8oQlf/9dJoY=";
   };
 
+  build-system = [ setuptools ];
+
   # there are no tests
   doCheck = false;
 
@@ -25,4 +30,4 @@ buildPythonPackage rec {
     license = lib.licenses.mit;
     maintainers = with lib.maintainers; [ turion ];
   };
-}
+})