Install pkg-config and update all nixpkgs
diff --git a/src/nix/system/pkg-config.nix b/src/nix/system/pkg-config.nix
new file mode 100644
index 0000000..cc0d6d6
--- /dev/null
+++ b/src/nix/system/pkg-config.nix
@@ -0,0 +1,5 @@
+{ pkgs, ... }: {
+  environment.systemPackages = [
+    pkgs.pkg-config
+  ];
+}