diff --git a/flake.nix b/flake.nix
index b6726ec..4366f33 100644
--- a/flake.nix
+++ b/flake.nix
@@ -8,62 +8,27 @@
 
   outputs = { self, nixpkgs, utils }: {
 
+    overlay = final: prev:
+      let scripts = prev.callPackage ./scripts.nix { }; in
+      {
+        inherit (scripts) format update test-develop dvt;
+      };
+
     templates = import ./templates.nix;
 
   } // utils.lib.eachDefaultSystem (system:
     let
-      pkgs = import nixpkgs { inherit system; };
-
-      inherit (pkgs) mkShell writeScriptBin;
-
-      run = pkg: "${pkgs.${pkg}}/bin/${pkg}";
-
-      dvt = writeScriptBin "dvt"
-        ''
-          if [ -z $1 ]; then
-            echo "no template specified"
-            exit 1
-          fi
-          TEMPLATE=$1
-          ${run "nix"} \
-            --experimental-features 'nix-command flakes' \
-            flake init \
-            --template \
-            "github:efishery/dvt#''${TEMPLATE}"
-        '';
-
-      format = writeScriptBin "format"
-        ''
-          ${run "nixpkgs-fmt"} **/*.nix
-        '';
-
-      update = writeScriptBin "update"
-        ''
-          for dir in `ls -d */`; do
-            (
-              cd $dir
-              ${run "nix"} flake update # Update flake.lock 
-              ${run "nix"} develop $dir # Make sure this work after update
-            )
-          done
-        '';
-
-      test-develop = writeScriptBin "test-develop"
-        ''
-          for dir in `ls -d */`; do
-            (
-              ${run "nix"} develop $dir # Make sure this work after update
-              sleep 0.2
-            )
-          done
-        '';
+      overlays = [ (self.overlay) ];
+      pkgs = import nixpkgs { inherit system overlays; };
     in
     {
-      devShells.default = mkShell { buildInputs = [ format update ]; };
+      devShells.default = pkgs.mkShell { buildInputs = with pkgs; [ format update ]; };
 
       packages = {
-        default = dvt;
-        inherit dvt test-develop;
+        dvt-init = pkgs.dvt;
+        dvt-format = pkgs.format;
+        dvt-update = pkgs.update;
+        inherit (pkgs) test-develop;
       };
     });
 }
diff --git a/scripts.nix b/scripts.nix
new file mode 100644
index 0000000..b17dd52
--- /dev/null
+++ b/scripts.nix
@@ -0,0 +1,43 @@
+{ writeScriptBin, nix, nixpkgs-fmt }:
+{
+  update = writeScriptBin "update"
+    ''
+      for dir in `ls -d */`; do
+        (
+          cd $dir
+          ${nix}/bin/nix flake update # Update flake.lock 
+          ${nix}/bin/nix develop $dir # Make sure this work after update
+        )
+      done
+    '';
+
+  test-develop = writeScriptBin "test-develop"
+    ''
+      for dir in `ls -d */`; do
+        (
+          ${nix}/bin/nix develop $dir # Make sure this work after update
+          sleep 0.2
+        )
+      done
+    '';
+
+  format = writeScriptBin "format"
+    ''
+      ${nixpkgs-fmt}/bin/nixpkgs-fmt **/*.nix
+    '';
+
+  dvt = writeScriptBin "dvt"
+    ''
+      if [ -z $1 ]; then
+        echo "no template specified"
+        exit 1
+      fi
+      TEMPLATE=$1
+      ${nix}/bin/nix \
+        --experimental-features 'nix-command flakes' \
+        flake init \
+        --template \
+        "github:efishery/dvt#''${TEMPLATE}"
+    '';
+}
+