Add nixfmt formatter

flake.lock

@@ -17,11 +17,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1640223855,
-        "narHash": "sha256-2bOGDrou/P0E85O5CzcZcHrvDBR78kRIwSPMlaLnFb8=",
+        "lastModified": 1721369373,
+        "narHash": "sha256-KomTFhD1yPKYvU7cqJGBRyQACfmGJMMkUWJpvw3K7B8=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "e7f5c0a08e442ed5772852b9f832d5d716020ebf",
+        "rev": "9d5188abf958325668881e99aa74866b69214639",
         "type": "github"
       },
       "original": {

flake.nix

@@ -1,10 +1,15 @@
 {
   description = "A flake of MOTD files.";
 
-  inputs.nixpkgs.url = github:NixOS/nixpkgs;
-  inputs.flake-utils.url = github:numtide/flake-utils;
+  inputs.nixpkgs.url = "github:NixOS/nixpkgs";
+  inputs.flake-utils.url = "github:numtide/flake-utils";
 
-  outputs = { self, nixpkgs, flake-utils }:
+  outputs =
+    {
+      self,
+      nixpkgs,
+      flake-utils,
+    }:
     let
       motdFiles = {
         "40k" = ./40k-thought-for-the-day.txt;
@@ -13,7 +18,8 @@
         discordium = ./discordium.txt;
       };
     in
-    flake-utils.lib.eachDefaultSystem (system:
+    flake-utils.lib.eachDefaultSystem (
+      system:
       let
         pkgs = nixpkgs.legacyPackages.${system};
         motd = pkgs.stdenv.mkDerivation {
@@ -22,17 +28,15 @@
           builder = builtins.toFile "motd-builder.sh" ''
             source $stdenv/setup
             mkdir -p $out
-            ${builtins.foldl'
-              (a: b: "${a}\n${b}")
-              ""
-              (map
-                (attr: "cp ${motdFiles.${attr}} $out/${attr}.txt")
-                (builtins.attrNames motdFiles))}
+            ${builtins.foldl' (a: b: "${a}\n${b}") "" (
+              map (attr: "cp ${motdFiles.${attr}} $out/${attr}.txt") (builtins.attrNames motdFiles)
+            )}
           '';
         };
       in
       {
         defaultPackage = motd;
+        formatter = pkgs.nixfmt-rfc-style;
       }
     );
 }