Add google-fonts package to flake

flake.lock

@@ -152,7 +152,8 @@
         "nix-wsl": "nix-wsl",
         "nixpkgs": "nixpkgs",
         "nixpkgs-unstable": "nixpkgs-unstable",
-        "pkg-android-tools": "pkg-android-tools"
+        "pkg-android-tools": "pkg-android-tools",
+        "systems": "systems_2"
       }
     },
     "systems": {
@@ -169,6 +170,21 @@
         "repo": "default",
         "type": "github"
       }
+    },
+    "systems_2": {
+      "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",

flake.nix

@@ -6,6 +6,9 @@
                  # ^^^^^^^^^^^^^ this part is optional
     nixpkgs-unstable.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
 
+    # this seems to be a popular way to declare systems
+    systems.url = "github:nix-systems/default";
+
     home-manager = {
       url = "github:nix-community/home-manager/release-23.11";
       inputs.nixpkgs.follows = "nixpkgs";
@@ -51,6 +54,8 @@
       inherit username mobileTimeZone self;
     };
 
+    # funciton to generate packages for each system
+    eachSystem = lib.genAttrs (import inputs.systems);
 
     # This function produces a module that adds the home-manager module to the
     # system and configures the given module to the user's Home Manager
@@ -138,6 +143,7 @@
     # (extraS|s)pecialArgs to pass variables
     nixosModules = (import ./modules/nixos) moduleInputs;
     homeManagerModules = (import ./modules/home-manager) moduleInputs;
+    packages = eachSystem (system: import ./pkgs { inherit nixpkgs system; });
 
     nixosConfigurations = {
       slab = mkSystem {

pkgs/default.nix

@@ -0,0 +1,8 @@
+{ nixpkgs, system, ... }:
+let
+  pkgs = import nixpkgs { inherit system; };
+  inherit (pkgs) callPackage;
+in
+{
+  google-fonts = callPackage ./google-fonts { };
+}

pkgs/google-fonts/default.nix

@@ -0,0 +1,70 @@
+{ lib
+, stdenvNoCC
+, fetchFromGitHub
+, fonts ? []
+}:
+
+stdenvNoCC.mkDerivation {
+  pname = "google-fonts";
+  version = "unstable-2023-10-20";
+
+  # Adobe Blank is split out in a separate output,
+  # because it causes crashes with `libfontconfig`.
+  # It has an absurd number of symbols
+  outputs = [ "out" "adobeBlank" ];
+
+  src = fetchFromGitHub {
+    owner = "google";
+    repo = "fonts";
+    rev = "990be3ed8f77e31c26bf07b148d6a74b8e6241cf";
+    sha256 = "sha256-ffLXzaniHkWxGQpvlJpiO6/SAdbI3FONgTaq8Xu+WY0=";
+  };
+
+  postPatch = ''
+    # These directories need to be removed because they contain
+    # older or duplicate versions of fonts also present in other
+    # directories. This causes non-determinism in the install since
+    # the installation order of font files with the same name is not
+    # fixed.
+    rm -rv ofl/cabincondensed \
+      ofl/signikanegative \
+      ofl/signikanegativesc \
+      ofl/*_todelist \
+      axisregistry/tests/data
+
+    if find . -name "*.ttf" | sed 's|.*/||' | sort | uniq -c | sort -n | grep -v '^.*1 '; then
+      echo "error: duplicate font names"
+      exit 1
+    fi
+  '';
+
+  dontBuild = true;
+
+  # The font files are in the fonts directory and use three naming schemes:
+  # FamilyName-StyleName.ttf, FamilyName[param1,param2,...].ttf, and
+  # FamilyName.ttf. This installs all fonts if fonts is empty and otherwise
+  # only the specified fonts by FamilyName.
+  fonts = map (font: builtins.replaceStrings [" "] [""] font) fonts;
+  installPhase = ''
+    adobeBlankDest=$adobeBlank/share/fonts/truetype
+    install -m 444 -Dt $adobeBlankDest ofl/adobeblank/AdobeBlank-Regular.ttf
+    rm -r ofl/adobeblank
+    dest=$out/share/fonts/truetype
+  '' + (if fonts == [] then ''
+    find . -name '*.ttf' -exec install -m 444 -Dt $dest '{}' +
+  '' else ''
+    for font in $fonts; do
+      find . \( -name "$font-*.ttf" -o -name "$font[*.ttf" -o -name "$font.ttf" \) -exec install -m 444 -Dt $dest '{}' +
+    done
+  '');
+
+  meta = with lib; {
+    homepage = "https://fonts.google.com";
+    description = "Font files available from Google Fonts";
+    license = with licenses; [ asl20 ofl ufl ];
+    platforms = platforms.all;
+    hydraPlatforms = [];
+    maintainers = with maintainers; [ manveru ];
+    sourceProvenance = [ sourceTypes.binaryBytecode ];
+  };
+}