Add unpack utility

configuration/lib/unpack.nix

@@ -0,0 +1,11 @@
+{ pkgs, ... }:
+	sourceArchive:
+		pkgs.stdenv.mkDerivation {
+			name = "unpack-temp";
+			src = sourceArchive;
+
+			buildCommand = ''
+				mkdir -p $out
+				tar -xzvf $src -C $out
+			'';
+		}