Fix nix.dev (#1142)

The nix.dev flake changed the output schema in

NixOS/nix.dev@957bda7

This failed the last attempted automated CI update:

https://github.com/NixOS/nixos-homepage/actions/runs/6700205463/job/18205745665

flake.nix

@@ -146,7 +146,7 @@ rec {
                 "NIXOS_AMIS=${nixosAmis}"
                 "NIX_PILLS_MANUAL_IN=${nixPills.html-split}/share/doc/nix-pills"
                 "NIX_PILLS_MANUAL_EPUB=${nixPills.epub}/share/doc/nix-pills/nix-pills.epub"
-                "NIX_DEV_MANUAL_IN=${nix-dev.defaultPackage.${system}}"
+                "NIX_DEV_MANUAL_IN=${nix-dev.packages.${system}.default}"
 
                 "-j 1"
               ];
@@ -174,7 +174,7 @@ rec {
               export NIXOS_AMIS="${nixosAmis}"
               export NIX_PILLS_MANUAL_IN="${nixPills.html-split}/share/doc/nix-pills"
               export NIX_PILLS_MANUAL_EPUB="${nixPills.epub}/share/doc/nix-pills/nix-pills.epub"
-              export NIX_DEV_MANUAL_IN="${nix-dev.defaultPackage.${system}}"
+              export NIX_DEV_MANUAL_IN="${nix-dev.packages.${system}.default}"
 
               rm -f site-styles/common-styles
               ln -s ${nixos-common-styles.packages."${system}".commonStyles} site-styles/common-styles

scripts/update.sh

@@ -4,6 +4,7 @@ set -e
 
 echo "Updating flake inputs..."
 nix flake lock \
+  --extra-experimental-features 'nix-command flakes' \
   --update-input released-nixpkgs-unstable \
   --update-input released-nixpkgs-stable \
   --update-input released-nix-unstable \
@@ -12,4 +13,6 @@ nix flake lock \
   --update-input nix-dev
 
 echo "Updating blog..."
-nix develop --command update-blog --output-dir blog/
+nix develop \
+  --extra-experimental-features 'nix-command flakes' \
+  --command update-blog --output-dir blog/