feat: build container via nix in CI

.github/workflows/Container.yaml

@@ -0,0 +1,29 @@
+name: Container
+
+on:
+  - push
+
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}
+  TAG: ${{ github.ref_name }}
+
+jobs:
+  Build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Nix
+        uses: DeterminateSystems/nix-installer-action@v10
+      - name: Cache
+        uses: DeterminateSystems/magic-nix-cache-action@v4
+      - name: Build
+        run: nix build -L .#container
+      - name: Login
+        run: nix run nixpkgs#skopeo -- login $REGISTRY --username ${{ github.actor }} --password ${{ secrets.GITHUB_TOKEN }}
+      - name: Push
+        run: nix run nixpkgs#skopeo -- copy docker-archive:result docker://$REGISTRY/$IMAGE_NAME:$TAG
+      - name: Push latest tag
+        if: ${{ github.ref_type == 'tag' }}
+        run: nix run nixpkgs#skopeo -- copy docker://$REGISTRY/$IMAGE_NAME:$TAG docker://$REGISTRY/$IMAGE_NAME:latest

flake.nix

@@ -51,7 +51,14 @@
           container = pkgs.dockerTools.buildLayeredImage {
             name = "d4v2";
             contents = [ self.packages.${system}.d4 ];
-            config.Entrypoint = [ "/bin/d4" ];
+            config = {
+              Entrypoint = [ "/bin/d4" ];
+              Labels = {
+                "org.opencontainers.image.source" = "https://github.com/SoftVarE-Group/d4v2";
+                "org.opencontainers.image.description" = "A CNF to d-DNNF compiler";
+                "org.opencontainers.image.licenses" = "LGPL-2.1-or-later";
+              };
+            };
           };
 
           mt-kahypar = pkgs.stdenv.mkDerivation {