diff --git a/checks/default.nix b/checks/default.nix
new file mode 100644
index 0000000..a816263
--- /dev/null
+++ b/checks/default.nix
@@ -0,0 +1,5 @@
+{ self, pkgs }:
+
+{
+  bird = import ./bird.nix { inherit self pkgs; };
+}
diff --git a/flake.lock b/flake.lock
index 0452ae9..53ef4af 100644
--- a/flake.lock
+++ b/flake.lock
@@ -1,5 +1,23 @@
 {
   "nodes": {
+    "flake-utils": {
+      "inputs": {
+        "systems": "systems"
+      },
+      "locked": {
+        "lastModified": 1726560853,
+        "narHash": "sha256-X6rJYSESBVr3hBoH0WbKE5KvhPU5bloyZ2L4K60/fPQ=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "c1dfcf08411b08f6b8615f7d8971a2bfa81d5e8a",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1730963269,
@@ -18,8 +36,24 @@
     },
     "root": {
       "inputs": {
+        "flake-utils": "flake-utils",
         "nixpkgs": "nixpkgs"
       }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
     }
   },
   "root": "root",
diff --git a/flake.nix b/flake.nix
index 8b2673b..91b257c 100644
--- a/flake.nix
+++ b/flake.nix
@@ -1,32 +1,24 @@
 {
   inputs = {
     nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.05";
+    flake-utils.url = "github:numtide/flake-utils";
   };
 
-  outputs = { self, nixpkgs, ... }:
-    let
-      systems = [
-        "x86_64-linux"
-        # "aarch64-linux"
-      ];
-
-    in
-    {
+  outputs = { self, nixpkgs, flake-utils, ... }:
+    flake-utils.lib.eachDefaultSystem
+      (system:
+        let
+          pkgs = (import nixpkgs) {
+            inherit system;
+          };
+        in
+        {
+          checks = import ./checks { inherit self pkgs; };
+        }
+      ) // {
       nixosModules = rec {
         bird = ./modules;
         default = bird;
       };
-
-      checks = builtins.listToAttrs (map
-        (system: {
-          name = system;
-          value = {
-            bird = import ./checks/bird.nix {
-              inherit self;
-              pkgs = nixpkgs.legacyPackages.${system};
-            };
-          };
-        })
-        systems);
     };
 }
diff --git a/modules/default.nix b/modules/default.nix
index abec0c3..14ceee2 100644
--- a/modules/default.nix
+++ b/modules/default.nix
@@ -10,23 +10,27 @@ in
     };
 
     protocols = lib.mkOption {
-      type = with lib.types; attrsOf str;
+      type = with lib.types; attrsOf lines;
     };
   };
 
   config = lib.mkIf cfg.enable {
     services.bird2 = {
-      config = ''
-        router id ${cfg.routerId};
-
-        ${builtins.concatStringsSep "\n" (builtins.attrValues
-          (builtins.mapAttrs
+      config =
+        let
+          protocols = lib.mapAttrsToList
             (name: conf: ''
               protocol ${name} {
                 ${conf}
               }
-            '') cfg.protocols))}
-      '';
+            '')
+            cfg.protocols;
+        in
+        ''
+          router id ${cfg.routerId};
+
+          ${builtins.concatStringsSep "\n" protocols}
+        '';
     };
   };
 }