diff --git a/pkgs/tools/misc/urn-timer/default.nix b/pkgs/tools/misc/urn-timer/default.nix
index 0b75657fb121..ad0c271fda66 100644
--- a/pkgs/tools/misc/urn-timer/default.nix
+++ b/pkgs/tools/misc/urn-timer/default.nix
@@ -12,7 +12,7 @@
 
 stdenv.mkDerivation {
   pname = "urn-timer";
-  version = "unstable-2024-03-05";
+  version = "0-unstable-2024-03-05";
 
   src = fetchFromGitHub {
     owner = "paoloose";