diff --git a/bsc/cn6/default.nix b/bsc/cn6/default.nix
index 941e4e1..7263c1a 100644
--- a/bsc/cn6/default.nix
+++ b/bsc/cn6/default.nix
@@ -18,6 +18,7 @@ stdenv.mkDerivation rec {
   src = builtins.fetchGit {
     url = "ssh://git@bscpm03.bsc.es/rarias/cn6.git";
     ref = "master";
+    rev = "c72c3b66b720c2a33950f536fc819051c8f20a69";
   };
 
   makeFlags = [ "PREFIX=$(out)" ];