diff --git a/pkgs/development/python-modules/flet/default.nix b/pkgs/development/python-modules/flet/default.nix
index 815d43c18e03..aafc2f957ec0 100644
--- a/pkgs/development/python-modules/flet/default.nix
+++ b/pkgs/development/python-modules/flet/default.nix
@@ -1,6 +1,7 @@
 { lib
 , buildPythonPackage
 , fetchPypi
+, pythonRelaxDepsHook
 
 # build-system
 , poetry-core
@@ -22,7 +23,7 @@
 buildPythonPackage rec {
   pname = "flet";
   version = "0.18.0";
-  format = "pyproject";
+  pyproject = true;
 
   src = fetchPypi {
     inherit pname version;
@@ -31,6 +32,11 @@ buildPythonPackage rec {
 
   nativeBuildInputs = [
     poetry-core
+    pythonRelaxDepsHook
+  ];
+
+  pythonRelaxDeps = [
+    "websockets"
   ];
 
   propagatedBuildInputs = [