diff --git a/.envrc b/.envrc
new file mode 100644
index 0000000..3550a30
--- /dev/null
+++ b/.envrc
@@ -0,0 +1 @@
+use flake
diff --git a/.gitignore b/.gitignore
index d787b70..052de26 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 /target
 /result
+/.direnv
diff --git a/flake.nix b/flake.nix
index 0f99669..6ae3357 100644
--- a/flake.nix
+++ b/flake.nix
@@ -28,7 +28,11 @@
       pkgs = nixpkgs.legacyPackages.${system};
     in {
       default = pkgs.mkShell {
-        packages = [pkgs.cargo-insta];
+        packages = [
+          pkgs.cargo-insta
+          pkgs.cargo-udeps
+          pkgs.mold
+        ];
       };
     });
   };