{
  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/nixpkgs-unstable";

    flake-utils.url = "github:numtide/flake-utils";
  };

  outputs = { self, flake-utils, nixpkgs }: flake-utils.lib.eachDefaultSystem (system:
    let
      pkgs = nixpkgs.legacyPackages.${system};
    in
    rec {
      packages = nixpkgs.lib.mapAttrs
        (name: value: pkgs.python3Packages.callPackage value { })
        {
          lunr =
            { buildPythonPackage, fetchPypi, future, six, mock, pytest }:

            buildPythonPackage rec {
              pname = "lunr";
              version = "0.5.8";

              src = fetchPypi {
                inherit pname version;
                sha256 = "0vn2j5iyy40sv0f4v8nin5n5xs4a020g6gcbcgfpbxzgk0xhdyy4";
              };

              propagatedBuildInputs = [
                future
                six
              ];

              checkInputs = [
                mock
                pytest
              ];
            };

          # FIXME: use nixpkgs’s mkdocs once it is ≥1.1
          mkdocs =
            { buildPythonPackage
            , fetchPypi
            , backports_tempfile
            , click
            , jinja2
            , livereload
            , markdown
            , nltk
            , pyyaml
            , tornado
            }:

            buildPythonPackage rec {
              pname = "mkdocs";
              version = "1.1.2";

              src = fetchPypi {
                inherit pname version;
                sha256 = "0fgv5zawpyyv0vd4j5y8m4h058lh9jkwfcm0xy4pg7dr09a1xdph";
              };

              propagatedBuildInputs = [
                backports_tempfile
                click
                jinja2
                livereload
                markdown
                nltk
                pyyaml
                tornado

                packages.lunr
              ];

              doCheck = false; # circular depdendency
            };

          pymdown-extensions =
            { buildPythonPackage, fetchPypi, markdown }:

            buildPythonPackage rec {
              pname = "pymdown-extensions";
              version = "8.0.1";

              src = fetchPypi {
                inherit pname version;
                sha256 = "07p5xks6qf73nbv0qb7jrspkpmxdyr7dpxv3rnkh9p2b5l2h99wv";
              };

              propagatedBuildInputs = [
                markdown
              ];

              doCheck = false; # they fail?
            };

          mkdocs-material-extensions =
            { buildPythonPackage, fetchPypi }:

            buildPythonPackage rec {
              pname = "mkdocs-material-extensions";
              version = "1.0.1";

              src = fetchPypi {
                inherit pname version;
                sha256 = "13y617sql4hqs376c3dfcb6v7q41km9x7fh52k3f74a2brzzniv9";
              };

              # circular dependency
              doCheck = false;
              postPatch = ''
                sed -i 's/mkdocs-material>=5.0.0//' requirements/project.txt
              '';
            };

          mkdocs-material =
            { buildPythonPackage, fetchPypi, markdown, pygments }:

            buildPythonPackage rec {
              pname = "mkdocs-material";
              version = "6.1.2";

              src = fetchPypi {
                inherit pname version;
                sha256 = "0yifc1df94rsaxy72hqnhjkv4c50c30j5kg0yxybkxy07p7kafic";
              };

              propagatedBuildInputs = [
                markdown
                pygments

                packages.mkdocs
                packages.mkdocs-material-extensions
                packages.pymdown-extensions
              ];
            };

          iosevka-web =
            { stdenv, fetchzip }:

            stdenv.mkDerivation rec {
              pname = "iosevka-web";
              version = "3.7.1";

              src = fetchzip {
                url = "https://github.com/be5invis/Iosevka/releases/download/v${version}/pkg-iosevka-${version}.zip";
                sha256 = "0d012aqfnyqlpl4smfa2x2qz2qmbbfxb6jr4awv8gp6r359rc9k1";
                stripRoot = false;
              };

              dontBuild = true;

              installPhase = ''
                mkdir -p $out
                cp -r woff woff2 ttf *.css $out
              '';
            };

          wiki =
            { stdenv }:

            stdenv.mkDerivation {
              name = "wiki";

              src = self;

              buildPhase = ''
                mkdocs build -d $out
                echo "doc wiki $out" >> $out/nix-support/hydra-build-products
              '';

              installPhase = ''
                mkdir -p $out/assets/fonts
                ln -s ${packages.iosevka-web} $out/assets/fonts/iosevka
              '';

              nativeBuildInputs = [
                packages.mkdocs
                packages.mkdocs-material
              ];
            };
        };

      defaultPackage = packages.wiki;

      apps = {
        serve = pkgs.writeShellScriptBin "serve" ''
          ${pkgs.miniserve}/bin/miniserve --index index.html ${packages.wiki}
        '';
      };

      # My hydra only has x86_64-linux builders
      hydraJobs =
        if builtins.elem system [ "x86_64-linux" ]
        then {
          build = packages.wiki;
        }
        else { };
    });
}