diff --git a/pkgs/development/python-modules/dulwich/default.nix b/pkgs/development/python-modules/dulwich/default.nix
index 35f98ab6eb6d..5ce01aaad1b5 100644
--- a/pkgs/development/python-modules/dulwich/default.nix
+++ b/pkgs/development/python-modules/dulwich/default.nix
@@ -30,7 +30,7 @@ buildPythonPackage rec {
   src = fetchFromGitHub {
     owner = "jelmer";
     repo = "dulwich";
-    rev = "refs/tags/${version}";
+    rev = "refs/tags/${pname}-${version}";
     hash = "sha256-bf3ZUMX4afpdTBpFnx0HMyzCNG6V/p4eOl36djxGbtk=";
   };