builtins.fetchTarball {url="https://github.com/NixOS/nixpkgs-channels/archive/6feee80de0920fbff16305f9c3a3f93d4f38e5da.tar.gz"; sha256="06rcv6p2bqpz3i9n9chjfxsz21yl0lqmamvmdpaj0lcb3ihc4pir";}