diff --git a/pkgs/development/python-modules/fastcore/default.nix b/pkgs/development/python-modules/fastcore/default.nix
index b7fc364958dd..e86013605e7b 100644
--- a/pkgs/development/python-modules/fastcore/default.nix
+++ b/pkgs/development/python-modules/fastcore/default.nix
@@ -8,7 +8,7 @@
 
 buildPythonPackage rec {
   pname = "fastcore";
-  version = "1.4.1";
+  version = "1.4.2";
   format = "setuptools";
 
   disabled = pythonOlder "3.8";
@@ -16,8 +16,8 @@ buildPythonPackage rec {
   src = fetchFromGitHub {
     owner = "fastai";
     repo = pname;
-    rev = version;
-    sha256 = "sha256-qZsCsMwZxJsnznQ/C1SUPexkquv0tIyCkNYL5f2k0FU=";
+    rev = "refs/tags/${version}";
+    sha256 = "sha256-0q+qFrfMsXkwgu08igt2kHZ9c3/aqz/inCpJXkPZsdg=";
   };
 
   propagatedBuildInputs = [