diff --git a/pkgs/development/python-modules/gym/default.nix b/pkgs/development/python-modules/gym/default.nix
index b207e7ca239..ea920663846 100644
--- a/pkgs/development/python-modules/gym/default.nix
+++ b/pkgs/development/python-modules/gym/default.nix
@@ -5,11 +5,11 @@
 
 buildPythonPackage rec {
   pname = "gym";
-  version = "0.12.0";
+  version = "0.12.1";
 
   src = fetchPypi {
     inherit pname version;
-    sha256 = "0ggac8a8qk06wplwg5xsisn9id3lis9qslri7m9rz22khlyl7z4j";
+    sha256 = "f8bee3672759aeec4271169dcbb2afc069b898c7f92882d965c59be8085f2b35";
   };
 
   propagatedBuildInputs = [