{
  description = "Mobilizon fork for potsda.mn";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    nix-filter.url = "github:numtide/nix-filter";
  };

  outputs = { self, nixpkgs, nix-filter }:
    let
      forAllSystems = f: nixpkgs.lib.genAttrs
        [ "x86_64-linux" "aarch64-linux" ]
        (system: f system);
      nixpkgsFor = forAllSystems (
        system:
        import nixpkgs { inherit system; }
      );
      filter = nix-filter.lib;
    in
    {

      packages = forAllSystems (system:
        let
          pkgs = nixpkgsFor.${system};
        in
        {
          mobilizon = pkgs.callPackage ./. {
            src = filter {
              root = ./.;
              exclude = [
                (filter.matchExt "nix")
                "js"
              ];
            };
            src-config = ./config;
            mobilizon-js = self.packages.x86_64-linux.mobilizon-frontend;
          };

          mobilizon-frontend = pkgs.callPackage ./js { inherit filter; };

          default = self.packages.x86_64-linux.mobilizon;

          # Update local Mobilizon definition
          update =
            pkgs.writeShellScriptBin "update" ''
              set -eou pipefail

              ${pkgs.mix2nix}/bin/mix2nix ./mix.lock > mix.nix
            '';
        });

      devShells = forAllSystems (system:
        let pkgs = nixpkgsFor.${system};
        in {
          default =
            pkgs.mkShell {
              buildInputs = with pkgs; [
                elixir
                mix2nix
                cmake
                imagemagick
                (yarn.override {
                  nodejs = nodejs-18_x;
                })
                yarn2nix
                nodejs-18_x
              ];
            };
        });

      checks = forAllSystems (system: {
        inherit (self.packages.${system}) mobilizon update;
      });

      lib = {
        # Patch the logos in the source tree of a mobilizon-frontend package before building.
        # Can be used to construct the argument for .overrideAttrs on mobilizon-frontend.
        mobilizonLogosOverride = icons:
          let
            inherit (icons) logo favicon;
          in
          old: {
            postPatch = ''
              cp '${logo}' src/assets/logo.svg

              magick convert \
                -resize x16 \
                -gravity center \
                -crop 16x16+0+0 \
                -flatten \
                -colors 256 \
                '${favicon}' \
                public/img/icons/favicon-16x16.png

              magick convert \
                -resize x32 \
                -gravity center \
                -crop 32x32+0+0 \
                -flatten \
                -colors 256 \
                '${favicon}' \
                public/img/icons/favicon-32x32.png


              magick convert \
                -resize x16 \
                -gravity center \
                -crop 16x16+0+0 \
                -flatten \
                -colors 256 \
                '${favicon}' \
                favicon-16x16.ico

              magick convert \
                -resize x32 \
                -gravity center \
                -crop 32x32+0+0 \
                -flatten \
                -colors 256 \
                '${favicon}' \
                favicon-32x32.ico

              magick convert \
                -resize x48 \
                -gravity center \
                -crop 48x48+0+0 \
                -flatten \
                -colors 256 \
                '${favicon}' \
                favicon-48x48.ico

              magick convert \
                favicon-16x16.ico \
                favicon-32x32.ico \
                favicon-48x48.ico \
                public/favicon.ico

              rm favicon-16x16.ico favicon-32x32.ico favicon-48x48.ico

              cp '${favicon}' public/img/icons/favicon.svg
              cp '${favicon}' public/img/icons/safari-pinned-tab.svg

              magick convert \
                '${favicon}' \
                -gravity center \
                -extent 630x350 \
                public/img/mobilizon_default_card.png

              magick convert \
                -background '#e08c96' \
                '${logo}' \
                -resize 366x108 \
                public/img/mobilizon_logo.png

            '' + nixpkgs.lib.concatMapStrings
              ({ resize, filename }: ''
                magick convert \
                  -resize x${resize} \
                  '${favicon}' \
                  public/img/icons/${filename}

              '')
              [
                { resize = "180"; filename = "apple-touch-icon.png"; }
                { resize = "180"; filename = "apple-touch-icon-180x180.png"; }
                { resize = "152"; filename = "apple-touch-icon-152x152.png"; }
                { resize = "120"; filename = "apple-touch-icon-120x120.png"; }
                { resize = "76"; filename = "apple-touch-icon-76x76.png"; }
                { resize = "60"; filename = "apple-touch-icon-60x60.png"; }
                { resize = "192"; filename = "android-chrome-192x192.png"; }
                { resize = "512"; filename = "android-chrome-512x512.png"; }
                { resize = "192"; filename = "android-chrome-maskable-192x192.png"; }
                { resize = "512"; filename = "android-chrome-maskable-512x512.png"; }
                { resize = "128"; filename = "badge-128x128.png"; }
                { resize = "144"; filename = "icon-144x144.png"; }
                { resize = "168"; filename = "icon-168x168.png"; }
                { resize = "256"; filename = "icon-256x256.png"; }
                { resize = "48"; filename = "icon-48x48.png"; }
                { resize = "72"; filename = "icon-72x72.png"; }
                { resize = "96"; filename = "icon-96x96.png"; }
                { resize = "144"; filename = "msapplication-icon-144x144.png"; }
                { resize = "150"; filename = "mstile-150x150.png"; }
                { resize = "192"; filename = "android-chrome-192x192.png"; }
                { resize = "512"; filename = "android-chrome-512x512.png"; }
                { resize = "192"; filename = "android-chrome-maskable-192x192.png"; }
                { resize = "512"; filename = "android-chrome-maskable-512x512.png"; }
              ];
          };

      };


    };
}