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

  outputs =
    { nixpkgs, ... }:
    let
      system = "x86_64-linux";
      pkgs = import nixpkgs { inherit system; };

      inherit (nixpkgs.lib) makeOverridable;
      inherit (pkgs.stdenvNoCC) mkDerivation;

      shared = mkDerivation {
        name = "talks-shared";
        src = ./src;

        installPhase = ''
          runHook preInstall

          mkdir $out
          cp -r fonts styles $out

          runHook postInstall
        '';
      };

      commonBuildInputs = with pkgs; [
        (python310.withPackages (p: with p; [ rst2pdf ]))
      ];

      mkTalk = makeOverridable (
        { name, src }:
        mkDerivation {
          inherit name shared src;

          buildInputs = commonBuildInputs;

          buildPhase = ''
            runHook preBuild

            mkdir $out

            rst2pdf slides.rst \
              --break-level 1 \
              --fit-background-mode scale \
              --font-path "${toString shared}/fonts" \
              --output "$out/slides.pdf" \
              --stylesheets bw,"${toString shared}/styles/opdavies-light"

            runHook postBuild
          '';
        }
      );

      talks = {
        build-configs = mkTalk {
          name = "build-configs";
          src = ./src/building-build-configs;
        };

        sculpin = mkTalk {
          name = "building-static-websites-sculpin";
          src = ./src/building-static-websites-sculpin;
        };

        tailwind-css = mkTalk {
          name = "taking-flight-with-tailwind-css";
          src = ./src/taking-flight-with-tailwind-css;
        };

        test-driven-drupal = mkTalk {
          name = "test-driven-drupal";
          src = ./src/test-driven-drupal;
        };
      };
    in
    {
      devShells.${system}.default =
        with pkgs;
        mkShell {
          packages =
            with pkgs;
            commonBuildInputs
            ++ [
              ghostscript
              just
              pdfpc
              texliveMedium # includes pdfjam
            ];
        };

      packages.${system} = {
        inherit shared;
      } // talks;

      formatter.${system} = pkgs.nixfmt-rfc-style;
    };
}