diff --git a/pkgs/development/python-modules/py-cid/default.nix b/pkgs/development/python-modules/py-cid/default.nix
index f6c48e04c861..2f75be74fc96 100644
--- a/pkgs/development/python-modules/py-cid/default.nix
+++ b/pkgs/development/python-modules/py-cid/default.nix
@@ -13,14 +13,14 @@
 
 buildPythonPackage rec {
   pname = "py-cid";
-  version = "0.3.0";
+  version = "0.4.0";
   format = "setuptools";
 
   src = fetchFromGitHub {
     owner = "ipld";
     repo = "py-cid";
-    rev = "v${version}";
-    hash = "sha256-aN7ee25ghKKa90+FoMDCdGauToePc5AzDLV3tONvh4U=";
+    tag = "v${version}";
+    hash = "sha256-IYjk7sajHFWgsOMxwk1tWvKtTfPN8vHoNeENQed7MiU=";
   };
 
   postPatch = ''