diff --git a/pkgs/games/cockatrice/default.nix b/pkgs/games/cockatrice/default.nix
index 3189f3946b7..fa3b906268d 100644
--- a/pkgs/games/cockatrice/default.nix
+++ b/pkgs/games/cockatrice/default.nix
@@ -2,7 +2,7 @@
 }:
 
 stdenv.mkDerivation rec {
-    name = "${pname}-${version}";
+    name = "${pname}-unstable-${version}";
     pname = "cockatrice";
     version = "2017-01-20";