diff --git a/.gitignore b/.gitignore
index 85ecc7c..0cca3b8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,11 +1,6 @@
 # Nix.
 /.direnv/
-
-# rst2df.
-/**/*.pdf
-/**/*.rst.build_temp
-/dist/*
-!/dist/.keep
+/result
 
 # pdfpc.
 /**/*.pdfpc
diff --git a/dist/.keep b/dist/.keep
deleted file mode 100644
index e69de29..0000000
diff --git a/flake.lock b/flake.lock
index 37be8ba..c621a52 100644
--- a/flake.lock
+++ b/flake.lock
@@ -2,16 +2,16 @@
   "nodes": {
     "nixpkgs": {
       "locked": {
-        "lastModified": 1725001927,
-        "narHash": "sha256-eV+63gK0Mp7ygCR0Oy4yIYSNcum2VQwnZamHxYTNi+M=",
+        "lastModified": 1741010256,
+        "narHash": "sha256-WZNlK/KX7Sni0RyqLSqLPbK8k08Kq7H7RijPJbq9KHM=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "6e99f2a27d600612004fbd2c3282d614bfee6421",
+        "rev": "ba487dbc9d04e0634c64e3b1f0d25839a0a68246",
         "type": "github"
       },
       "original": {
         "owner": "NixOS",
-        "ref": "nixos-24.05",
+        "ref": "nixos-unstable",
         "repo": "nixpkgs",
         "type": "github"
       }
diff --git a/flake.nix b/flake.nix
index 695a484..230a14c 100644
--- a/flake.nix
+++ b/flake.nix
@@ -1,25 +1,98 @@
 {
-  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.05";
+  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
 
   outputs =
     { nixpkgs, ... }:
     let
       system = "x86_64-linux";
-      pkgs = nixpkgs.legacyPackages.${system};
+      pkgs = import nixpkgs { inherit system; };
 
-      inherit (pkgs) mkShell nixfmt-classic;
-    in
-    {
-      devShells.${system}.default = mkShell {
-        packages = with pkgs; [
-          ghostscript
-          pdfpc
-          python310Packages.rst2pdf
-          texliveMedium # includes pdfjam
-          tree
-        ];
+      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
+        '';
       };
 
-      formatter.${system} = nixfmt-classic;
+      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.${system} = pkgs.nixfmt-rfc-style;
     };
 }
diff --git a/justfile b/justfile
new file mode 100644
index 0000000..428df9b
--- /dev/null
+++ b/justfile
@@ -0,0 +1,19 @@
+alias b := build
+
+_default:
+    just --list
+
+build:
+    #!/usr/bin/env bash
+    selected=$(nix flake show --json | jq --raw-output '.packages["x86_64-linux"] | keys[]' | grep -v shared | fzf)
+
+    nix build \
+      --json \
+      --print-build-logs \
+      .#"$selected"
+
+check:
+    nix flake check
+
+clean:
+    rm -frv result
diff --git a/run b/run
deleted file mode 100755
index 442a666..0000000
--- a/run
+++ /dev/null
@@ -1,107 +0,0 @@
-#!/usr/bin/env bash
-
-set -o errexit
-set -o nounset
-set -o pipefail
-
-PDF_FILENAME=slides.pdf
-RST_FILENAME="${RST_FILENAME:-slides.rst}"
-THUMBNAIL_FILENAME=thumbnail.jpg
-
-function clean {
-  rm -fr dist/*
-  touch dist/.keep
-
-  find . \
-    -type f \( -name "${PDF_FILENAME}*" -o -name *.build_temp -o -name ${THUMBNAIL_FILENAME} \) \
-    -delete
-}
-
-function generate {
-  generate:pdf "${@}"
-}
-
-function generate:pdf {
-  if [ "${1}" == "" ]; then
-    echo "Usage: ./${0##*/} ${FUNCNAME[0]} <talk-name>"
-    exit 1
-  fi
-
-  DIRECTORY_NAME=$1
-  shift 1
-  pushd "src/${DIRECTORY_NAME}"
-
-  rst2pdf "${RST_FILENAME}" \
-    --break-level 1 \
-    -e preprocess \
-    --fit-background-mode scale \
-    --font-path ../fonts \
-    --output "../../dist/${DIRECTORY_NAME}.pdf" \
-    --stylesheets ../styles/opdavies-light,tango \
-    "${@}"
-
-  popd
-
-  tree dist
-}
-
-# Generate JPG thumbnails of each slide in a presentation.
-function generate:thumbnail {
-  if [ "${1}" == "" ]; then
-    echo "Usage: ./${0##*/} ${FUNCNAME[0]} <talk-name>"
-    exit 1
-  fi
-
-  if [ ! -d "src/${1}" ]; then
-    echo "${1} not found"
-    exit 2
-  fi
-
-  generate:pdf "${1}"
-
-  mkdir -p "dist/${1}"
-
-  gs \
-    -dBATCH \
-    -dDownScaleFactor=3 \
-    -dNOPAUSE \
-    -r600 \
-    -sDEVICE=jpeg \
-    -sOutputFile="dist/${1}/%d.jpg" \
-    "dist/${1}.pdf"
-}
-
-function help {
-  printf "%s <task> [args]\n\nTasks:\n" "${0}"
-
-  compgen -A function | grep -v "^_" | cat -n
-
-  printf "\nExtended help:\n  Each task has comments for general usage\n"
-}
-
-# Create a new talk.
-function new {
-  if [ "${1}" == "" ]; then
-    echo "Usage: ./${0##*/} ${FUNCNAME[0]} <talk-name>"
-    exit 1
-  fi
-
-  if [[ -e "src/${1}" ]]; then
-    echo "Error: ${1} already exists."
-    exit 1
-  fi
-
-  mkdir -vp "src/${1}"
-
-  touch "src/${1}/slides.rst"
-}
-
-function present {
-  TALK_PATH=$1
-  shift 1
-
-  pdfpc "${@}" "dist/${TALK_PATH}.pdf"
-}
-
-TIMEFORMAT=$'\nTask completed in %3lR'
-time "${@:-help}"