Migrated from default.nix to configuration.nix

overlays/default.nix

@@ -0,0 +1,18 @@
+{ inputs, ...}: {
+  # This one brings our custom packages from the 'pkgs' directory
+  additions = final: prev: import ../pkgs final.pkgs;
+
+  # This one contains whatever you want to overlay
+  # You can change versions, add patches, set compilation flags, anything really.
+  # https://nixos.wiki/wiki/Overlays
+  modifications = final: prev: {
+  };
+
+  unstable-packages = final: _prev: {
+    unstable = import inputs.nixpkgs-unstable {
+      system = final.system;
+      config.allowUnfree = false;
+    };
+  };
+}
+