diff --git a/pkgs/servers/isso/default.nix b/pkgs/servers/isso/default.nix
index b9bce56d9fa0..4db8ac1f4034 100644
--- a/pkgs/servers/isso/default.nix
+++ b/pkgs/servers/isso/default.nix
@@ -3,16 +3,14 @@
 with python3Packages; buildPythonApplication rec {
 
   pname = "isso";
-  # Can not use 0.12.2 because of:
-  # https://github.com/posativ/isso/issues/617
-  version = "unstable-2020-09-14";
+  version = "0.12.4";
 
   # no tests on PyPI
   src = fetchFromGitHub {
     owner = "posativ";
     repo = pname;
-    rev = "f4d2705d4f1b51f444d0629355a6fcbcec8d57b5";
-    sha256 = "02jgfzq3svd54zj09jj7lm2r7ypqqjynzxa9dgnnm0pqvq728wzr";
+    rev = version;
+    sha256 = "16wjpz8r74fzjvzhl6by3sjc2g1riz8lh59ccgp14bns1yhsh2yi";
   };
 
   propagatedBuildInputs = [