Add :dev build

.github/workflows/dev.yml

@@ -0,0 +1,35 @@
+name: dev
+
+on:
+  push:
+    branches: [ master ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Get info
+      id: determine
+      run: echo "::set-output name=repo::${GITHUB_REPOSITORY,,}"
+    - uses: docker/setup-buildx-action@v1
+      id: buildx
+    - name: Cache Docker layers
+      uses: actions/cache@v2
+      with:
+        path: /tmp/.buildx-cache
+        key: ${{ runner.os }}-buildx-${{ github.sha }}
+        restore-keys: |
+          ${{ runner.os }}-buildx-
+    - name: Login to DockerHub
+      uses: docker/login-action@v1
+      with:
+        username: ${{ secrets.DOCKERHUB_USERNAME }}
+        password: ${{ secrets.DOCKERHUB_PASSWORD }}
+    - name: Build and push
+      uses: docker/build-push-action@v2
+      with:
+        build-args: ENVIRONMENT=local
+        push: true
+        tags: "${{ steps.determine.outputs.repo }}:dev"
+        cache-from: type=local,src=/tmp/.buildx-cache
+        cache-to: type=local,dest=/tmp/.buildx-cache