Use flake instead of shell

flake.lock

@@ -0,0 +1,41 @@
+{
+  "nodes": {
+    "flake-utils": {
+      "locked": {
+        "lastModified": 1644229661,
+        "narHash": "sha256-1YdnJAsNy69bpcjuoKdOYQX0YxZBiCYZo4Twxerqv7k=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "3cecb5b042f7f209c56ffd8371b2711a290ec797",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1647350163,
+        "narHash": "sha256-OcMI+PFEHTONthXuEQNddt16Ml7qGvanL3x8QOl2Aao=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "3eb07eeafb52bcbf02ce800f032f18d666a9498d",
+        "type": "github"
+      },
+      "original": {
+        "id": "nixpkgs",
+        "type": "indirect"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,26 @@
+{
+  description = "Wedding site for Chris & Scotia 2023.";
+
+  inputs = {
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs = inputs @ { self, nixpkgs, ... }:
+    inputs.flake-utils.lib.eachDefaultSystem (system:
+      let pkgs = nixpkgs.legacyPackages.${system};
+          weddingSiteDir = "$HOME/.local/source/wedding-site/public/";
+          weddingSiteTgt = "ubuntu@chrishayward.xyz:/var/www/wedding";
+          weddingSiteUpdate = pkgs.writeShellScriptBin "wedding-site-update" ''
+            ${pkgs.rsync}/bin/rsync -aP ${weddingSiteDir} ${weddingSiteTgt}
+          '';
+      in
+        rec {
+          devShell = pkgs.mkShell {
+            buildInputs = with pkgs; [
+              hugo
+              weddingSiteUpdate
+            ];
+          };
+        }
+    );
+}

shell.nix

@@ -1,17 +0,0 @@
-{ pkgs ? import <nixpkgs> { } }:
-
-let
-  myUpdateWeddingSite = pkgs.writeShellScriptBin "update-wedding-site" ''
-    ${pkgs.rsync}/bin/rsync -aP $HOME/.local/source/wedding-site/public/ ubuntu@chrishayward.xyz:/var/www/wedding
-  '';
-
-in
-with pkgs;
-mkShell {
-  buildInputs = [
-    pkgs.hugo
-    myUpdateWeddingSite
-  ];
-  shellHook = ''
-  '';
-}