diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..7c6482e
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,4 @@
+outputs/
+result
+result-*
+repl-result-*
diff --git a/flake.nix b/flake.nix
index 94ea2e8..69d772e 100644
--- a/flake.nix
+++ b/flake.nix
@@ -5,13 +5,13 @@
 
   outputs = { self, nixpkgs }: let
     system = "x86_64-linux";
-    myOverlay = import ./overlays/my-pkgs.nix;
+    myPkgs = import ./overlays/my-pkgs.nix;
     pkgs = import nixpkgs {
       inherit system;
-      overlays = [ myOverlay ];
+      overlays = [ myPkgs ];
     };
   in {
-    overlays = [ myOverlay ];
-    packages.${system} = pkgs;
+    overlays = { inherit myPkgs; };
+    packages.${system} = pkgs // { default = pkgs.hello-zmsun; };
   };
 }
diff --git a/pkgs/hello-zmsun/default.nix b/pkgs/hello-zmsun/default.nix
new file mode 100644
index 0000000..2c79c5c
--- /dev/null
+++ b/pkgs/hello-zmsun/default.nix
@@ -0,0 +1,60 @@
+{
+  callPackage,
+  lib,
+  stdenv,
+  fetchurl,
+  nixos,
+  testers,
+  versionCheckHook,
+  hello,
+}:
+
+stdenv.mkDerivation (finalAttrs: {
+  pname = "hello-zmsun";
+  version = "2.12.2";
+
+  src = fetchurl {
+    url = "mirror://gnu/hello/hello-${finalAttrs.version}.tar.gz";
+    hash = "sha256-WpqZbcKSzCTc9BHO6H6S9qrluNE72caBm0x6nc4IGKs=";
+  };
+
+  # The GNU Hello `configure` script detects how to link libiconv but fails to actually make use of that.
+  # Unfortunately, this cannot be a patch to `Makefile.am` because `autoreconfHook` causes a gettext
+  # infrastructure mismatch error when trying to build `hello`.
+  env = lib.optionalAttrs stdenv.hostPlatform.isDarwin {
+    NIX_LDFLAGS = "-liconv";
+  };
+
+  doCheck = true;
+
+  doInstallCheck = true;
+  nativeInstallCheckInputs = [
+    versionCheckHook
+  ];
+
+  # Give hello some install checks for testing purpose.
+  postInstallCheck = ''
+    stat "''${!outputBin}/bin/${finalAttrs.meta.mainProgram}"
+  '';
+
+  passthru.tests = {
+    version = testers.testVersion { package = hello; };
+  };
+
+  passthru.tests.run = callPackage ./test.nix { hello = finalAttrs.finalPackage; };
+
+  meta = {
+    description = "Program that produces a familiar, friendly greeting";
+    longDescription = ''
+      GNU Hello is a program that prints "Hello, world!" when you run it.
+      It is fully customizable.
+    '';
+    homepage = "https://www.gnu.org/software/hello/manual/";
+    changelog = "https://git.savannah.gnu.org/cgit/hello.git/plain/NEWS?h=v${finalAttrs.version}";
+    license = lib.licenses.gpl3Plus;
+    maintainers = with lib.maintainers; [ stv0g ];
+    mainProgram = "hello";
+    platforms = lib.platforms.all;
+    identifiers.cpeParts.vendor = "gnu";
+  };
+})