blog-pim/flake.nix

{
  description = "A very basic flake";

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

  outputs = { self, nixpkgs, flutils }: flutils.lib.eachDefaultSystem (system:
    let
      pkgs = nixpkgs.legacyPackages.${system};

      gems = pkgs.bundlerEnv {
        name = "blog-pim";
        gemdir = ./src;
      };

      patch-feed-date = pkgs.stdenv.mkDerivation {
        name = "path-feed-date";
        propagatedBuildInputs = [ pkgs.python3 ];
        dontUnpack = true;
        installPhase = "install -Dm755 ${./patch-feed-date.py} $out/bin/patch-feed-date";
      };
    in
    {
      packages.static-website = pkgs.stdenv.mkDerivation {
        name = "blog-pim";
        src = ./src;
        sourceRoot = "src";

        buildInputs = [
          gems
          gems.wrappedRuby
          patch-feed-date
        ];

        buildPhase = ''
          bundle exec jekyll build
        '';

        installPhase = ''
          mkdir -p $out
          cp -r _site/* $out/
          patch-feed-date --file _site/feed.xml > $out/feed.xml
        '';
      };
    });
}