feat: add nix-systems/default flake and remove systems module

flake.lock

@@ -157,9 +157,25 @@
         "import-tree": "import-tree",
         "make-shell": "make-shell",
         "nixpkgs": "nixpkgs",
+        "systems": "systems",
         "text": "text"
       }
     },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    },
     "text": {
       "locked": {
         "lastModified": 1751749699,

flake.nix

@@ -2,6 +2,8 @@
   inputs = {
     # nixos-unstable provides a binary cache for all packages.
     nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
+    # systems provides a list of supported nix systems.
+    systems.url = "github:nix-systems/default";
     # flake-parts lets us define flake modules.
     flake-parts = {
       url = "github:hercules-ci/flake-parts";
@@ -36,5 +38,12 @@
     };
   };
 
-  outputs = inputs: inputs.flake-parts.lib.mkFlake { inherit inputs; } (inputs.import-tree ./modules);
+  outputs =
+    inputs:
+    inputs.flake-parts.lib.mkFlake { inherit inputs; } (
+      (inputs.import-tree ./modules)
+      // {
+        systems = import inputs.systems;
+      }
+    );
 }

modules/systems.nix

@@ -1,3 +0,0 @@
-{
-  systems = [ "x86_64-linux" ];
-}