diff --git a/pkgs/development/python-modules/portpicker/default.nix b/pkgs/development/python-modules/portpicker/default.nix
index ff2e925ded3f..90ed4b34b707 100644
--- a/pkgs/development/python-modules/portpicker/default.nix
+++ b/pkgs/development/python-modules/portpicker/default.nix
@@ -6,6 +6,7 @@
 buildPythonPackage rec {
   pname = "portpicker";
   version = "1.4.0";
+  format = "pyproject";
 
   src = fetchPypi {
     inherit pname version;