update flake

Update CL:

.github/workflows/ci.yml

@@ -5,10 +5,13 @@ on:
   push:
     branches:
       - main
-
+      
 env:
   # Required to make some things output color
   TERM: ansi
+  REGISTRY: ghcr.io
+  REPOSITORY: ${{ github.repository }}
+  TAG: latest
 
 jobs:
   ci:
@@ -16,6 +19,10 @@ jobs:
 
     runs-on: ubuntu-latest
 
+    permissions:
+      contents: read
+      packages: write
+
     steps:
       - name: Sync repository
         uses: actions/checkout@v4
@@ -44,13 +51,13 @@ jobs:
         run: nix-env -f "<nixpkgs>" -i direnv -i nix-direnv
 
       - name: Pop/push downloaded crate cache
-        uses: actions/cache@v4
+        uses: actions/cache@v3
         with:
           key: downloaded-crates
           path: ~/.cargo
 
       - name: Pop/push compiled crate cache
-        uses: actions/cache@v4
+        uses: actions/cache@v3
         with:
           key: compiled-crates-${{runner.os}}
           path: target
@@ -63,3 +70,18 @@ jobs:
         run: |
           direnv allow
           direnv exec . engage
+      
+      - name: Log in to the Container registry
+        uses: docker/login-action@v3
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Build docker image
+        run: nix build .#oci-image
+      
+      - name: Push docker image to DockerHub
+        run: |
+          docker load < result
+          docker push ${{ env.REPOSITORY }}:${{ env.TAG }}