fix nix experimental feature

nixos/conf

@@ -20,7 +20,7 @@ peek() {
 }
 nix() {
     decrypt
-    peek nix "$@"
+    peek nix --extra-experimental-features nix-command "$@"
 }
 nix-build() {
     decrypt

nixos/roles/default.nix

@@ -37,6 +37,9 @@ in {
   nixpkgs.config.allowUnfree = true;
 
   #nix.buildCores = config.nix.maxJobs;
+  nix.extraOptions = ''
+    experimental-features = nix-command flakes
+  '';
 
   # Networking
   networking.enableIPv6 = true;