feat(nixos-testbed): Use Deertopia binary cache

flake.lock

@@ -531,7 +531,7 @@
         "nixpkgs": "nixpkgs_9"
       },
       "locked": {
-        "lastModified": 1739938885,
+        "lastModified": 1739936838,
         "narHash": "sha256-h19Bg+BTV/51MiCnKa3rN3QbRC74cBWjBHhDrpVgdXM=",
         "path": "/persist/dots/scripts/sydnix-cli",
         "type": "path"

hosts/nixos-testbed/configuration.nix

@@ -102,6 +102,22 @@
   #   ];
   # };
 
+  nix = {
+    settings = {
+      substituters = [
+        "https://cache.deertopia.net"
+        "https://nix-community.cachix.org"
+        "https://cache.nixos.org"
+      ];
+      trusted-public-keys = [
+        (builtins.readFile ../../public-keys/deertopia-cache.pub.pem)
+        "binarycache.example.com-1:dsafdafDFW123fdasfa123124FADSAD"
+        "nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs="
+      ];
+    };
+  };
+
+
   # This option defines the first version of NixOS you have installed on this
   # particular machine, and is used to maintain compatibility with application
   # data (e.g. databases) created on older NixOS versions.