feat(pkgs): Install custom kontemplate package

packages.nix

@@ -57,6 +57,7 @@ in {
     latest.rustChannels.stable.rust
 
     # Custom packages:
+    (import pkgs/kontemplate.nix)
     (import pkgs/nixfd.nix)
   ];
 }

pkgs/kontemplate.nix

@@ -0,0 +1,22 @@
+# Install the latest kontemplate version
+with import <nixpkgs> {};
+
+stdenv.mkDerivation {
+  name = "kontemplate-1.2.0";
+
+  src = fetchzip {
+    url = "https://github.com/tazjin/kontemplate/releases/download/v1.2.0/kontemplate-1.2.0-f8b6ad6-linux-amd64.tar.gz";
+    sha256 = "09siirhr1m9lc91bkw4h4l1qpnjnl03yr5m9mjfxdkp5gzmkcb9r";
+  };
+
+  installPhase = ''
+    mkdir -p $out/bin
+    mv kontemplate $out/bin/kontemplate
+  '';
+
+  meta = with stdenv.lib; {
+    description = "Extremely simple Kubernetes resource templates";
+    homepage = "http://kontemplate.works";
+    license = licenses.mit;
+  };
+}