{
  description = "Sewing Tools";

  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs";
    flake-utils.url = "github:numtide/flake-utils";
  };

  outputs =
    { self
    , nixpkgs
    , flake-utils
    }:
    (flake-utils.lib.eachDefaultSystem (system:
    let pkgs = nixpkgs.legacyPackages.${system};
    in {

      packages.valentina-061 = pkgs.libsForQt512.callPackage pkgs/valentina-0.6.1.nix { };
      packages.valentina = self.packages.${system}.valentina-061;

      packages.seamly2d = pkgs.libsForQt5.callPackage pkgs/seamly2d-2022-06-13.nix { };

      # nix build
      packages.default = self.packages.${system}.valentina;
      # TODO: Legacy attribute, drop soon
      defaultPackage = self.packages.${system}.default;

      devShells.default = pkgs.mkShell {
        buildInputs = [

          # building seamly2d and valentina
          pkgs.qt5.full
          pkgs.qtcreator
          pkgs.libGL
          pkgs.qt5.qtsvg
          pkgs.poppler_utils
          pkgs.qt5.qtxmlpatterns
          pkgs.qt5.qt3d
          pkgs.qt5.qmake

          # poster
          pkgs.imagemagick
          pkgs.ghostscript
          # A4 is 2480 x 3508 Pixel
          # A4 with 100px space on top bottom left and right is :  2280 x 3308 Pixel
          (pkgs.writers.writeBashBin "posterize" ''
            ${pkgs.imagemagick}/bin/convert -density 300 -depth 8 -quality 85 input.pdf input.png
            ${pkgs.imagemagick}/bin/convert input.png -crop 2280x3308  +repage  output_a4_%02d.png
            for file in output_a4_*
            do
              ${pkgs.imagemagick}/bin/convert \
                $file \
                -gravity center \
                -background gray \
                -extent 2480x3508 \
                final_$file
            done
            ${pkgs.imagemagick}/bin/convert final_*.png -quality 100 output.pdf
            rm -rf *.png
          '')
        ];
      };

    }));
}