add eval github action

Author: codebam

.github/workflows/nix-build.yml

@@ -0,0 +1,33 @@
+name: nix build .
+
+on:
+  push:
+    branches: [ "master" ]
+  pull_request:
+    branches: [ "master" ]
+
+  workflow_dispatch:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Install Nix
+        uses: cachix/install-nix-action@v27
+        with:
+          extra_nix_config: |
+            access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}
+            experimental-features = nix-command flakes
+
+      - name: nix eval .#nixosConfigurations.nixos-desktop
+        run: nix eval .#nixosConfigurations.nixos-desktop
+
+      - name: nix eval .#nixosConfigurations.nixos-laptop
+        run: nix eval .#nixosConfigurations.nixos-laptop
+
+      - name: nix eval .#nixosConfigurations.nixos-steamdeck
+        run: nix eval .#nixosConfigurations.nixos-steamdeck