diff --git a/pkgs/development/python-modules/immutabledict/default.nix b/pkgs/development/python-modules/immutabledict/default.nix
index 47e062ab35d6..3a98de5f1032 100644
--- a/pkgs/development/python-modules/immutabledict/default.nix
+++ b/pkgs/development/python-modules/immutabledict/default.nix
@@ -9,7 +9,7 @@
 
 buildPythonPackage rec {
   pname = "immutabledict";
-  version = "4.2.0";
+  version = "4.2.1";
   format = "pyproject";
 
   disabled = pythonOlder "3.7";
@@ -18,7 +18,7 @@ buildPythonPackage rec {
     owner = "corenting";
     repo = "immutabledict";
     rev = "refs/tags/v${version}";
-    hash = "sha256-NpNS8HAacgXm3rFtyd5uFgSURNbDf+YVS1aFx51kwEA=";
+    hash = "sha256-v2oOzvAa8KONZDQuxouai2B9d1RY4kZG/px2wl0KAyM=";
   };
 
   nativeBuildInputs = [ poetry-core ];