diff --git a/.github/workflows/push.yaml b/.github/workflows/master.yaml
similarity index 57%
rename from .github/workflows/push.yaml
rename to .github/workflows/master.yaml
index f1c188f..b12ec06 100644
--- a/.github/workflows/push.yaml
+++ b/.github/workflows/master.yaml
@@ -4,9 +4,13 @@ on:
   push:
     branches:
       - master
+  pull_request:
+    branches:
+      - master
 
 env:
-  IMAGE_NAME: notifier
+  DOCKER_REPO: ww24/calendar-notifier
+  IMAGE_NAME: calendar-notifier
   IMAGE_TAG: latest
 
 jobs:
@@ -15,16 +19,22 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v1
+      - uses: actions/cache@v2
+        with:
+          path: ~/go/pkg/mod
+          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+          restore-keys: |
+            ${{ runner.os }}-go-
       - uses: actions/setup-go@v1
         with:
-          go-version: "1.13"
+          go-version: "1.14"
       - name: setup env
         run: |
           echo "::set-env name=GOPATH::$(go env GOPATH)"
           echo "::add-path::$(go env GOPATH)/bin"
         shell: bash
       - name: Install go tools
-        run: cat tools.go | grep _ | awk -F '"' '{print $2}' | xargs -tI {} go install {}
+        run: cat tools.go | awk -F'"' '/_/ {print $2}' | xargs -tI {} go install {}
       - name: go generate
         run: go generate ./...
       - name: Check uncommitted changes
@@ -39,9 +49,8 @@ jobs:
       - run: go vet ./...
       - run: go test -v -race ./...
 
-  docker:
-    needs: test
-    name: Build and push docker image
+  docker_build_test:
+    name: Build docker image
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v1
@@ -67,7 +76,35 @@ jobs:
         run: |
           trivy -q --severity HIGH,CRITICAL --exit-code 1 \
             "docker.pkg.github.com/${GITHUB_REPOSITORY}/${IMAGE_NAME}:${IMAGE_TAG}"
-      - name: Push docker image
+
+  docker_push:
+    if: ${{ github.event_name == 'push' }}
+    needs: [test, docker_build_test]
+    name: Build and push docker image
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v1
+      - uses: actions/cache@v2
+        with:
+          path: /tmp/.buildx-cache
+          key: ${{ runner.os }}-buildx-${{ github.sha }}
+          restore-keys: |
+            ${{ runner.os }}-buildx-
+      - name: Docker login
+        env:
+          DOCKER_USER: ${{ secrets.DOCKER_USER }}
+          DOCKER_PASSWORD: ${{ secrets.DOCKER_PASSWORD }}
+        run: echo "${DOCKER_PASSWORD}" | docker login --username "${DOCKER_USER}" --password-stdin
+      - name: Build docker image and push (DockerHub)
+        run: |
+          docker buildx build \
+            --cache-from "type=local,src=/tmp/.buildx-cache" \
+            --cache-to "type=local,dest=/tmp/.buildx-cache" \
+            --platform linux/amd64,linux/arm64,linux/arm/v7,linux/arm/v6 \
+            --output "type=image,push=true" \
+            -t "${DOCKER_REPO}":${IMAGE_TAG} .
+      - name: Build docker image and push (GitHub)
         run: |
+          docker build -t "docker.pkg.github.com/${GITHUB_REPOSITORY}/${IMAGE_NAME}:${IMAGE_TAG}" .
           echo "${{ secrets.GITHUB_TOKEN }}" | docker login -u owner --password-stdin docker.pkg.github.com
           docker push "docker.pkg.github.com/${GITHUB_REPOSITORY}/${IMAGE_NAME}:${IMAGE_TAG}"
diff --git a/.github/workflows/pr.yaml b/.github/workflows/pr.yaml
deleted file mode 100644
index fdcfc1c..0000000
--- a/.github/workflows/pr.yaml
+++ /dev/null
@@ -1,65 +0,0 @@
-name: Test for PR
-
-on: pull_request
-
-env:
-  IMAGE_NAME: notifier
-  IMAGE_TAG: latest
-
-jobs:
-  test:
-    name: Test
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v1
-      - uses: actions/setup-go@v1
-        with:
-          go-version: "1.13"
-      - name: setup env
-        run: |
-          echo "::set-env name=GOPATH::$(go env GOPATH)"
-          echo "::add-path::$(go env GOPATH)/bin"
-        shell: bash
-      - name: Install go tools
-        run: cat tools.go | grep _ | awk -F '"' '{print $2}' | xargs -tI {} go install {}
-      - name: go generate
-        run: go generate ./...
-      - name: Check uncommitted changes
-        run: |
-          if [ -n "$(git status --porcelain)" ]; then
-              echo "uncommitted changes"
-              git status
-              exit 1
-          fi
-      - name: go lint
-        run: go list ./... | xargs golint -set_exit_status
-      - run: go vet ./...
-      - run: go test -v -race ./...
-
-  docker:
-    name: Build docker image
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v1
-      - name: Shellcheck
-        env:
-          SHELLCHECK_OPTS: -e SC2187
-        run: find . -name "*.sh" | xargs shellcheck
-      - name: Lint
-        run: |
-          docker run -v $(pwd):/working --rm hadolint/hadolint \
-          hadolint /working/Dockerfile \
-          --ignore DL3018
-      - name: Build docker image
-        run: docker build -t "docker.pkg.github.com/${GITHUB_REPOSITORY}/${IMAGE_NAME}:${IMAGE_TAG}" .
-      - name: Install trivy
-        run: |
-          sudo apt-get install --no-install-recommends apt-transport-https gnupg lsb-release
-          wget -qO - https://aquasecurity.github.io/trivy-repo/deb/public.key | sudo apt-key add -
-          echo deb https://aquasecurity.github.io/trivy-repo/deb $(lsb_release -sc) main | sudo tee -a /etc/apt/sources.list.d/trivy.list
-          sudo apt-get update
-          sudo apt-get install --no-install-recommends trivy
-      - name: Vulnerability Scan
-        run: |
-          trivy -q --severity HIGH,CRITICAL --exit-code 1 \
-            "docker.pkg.github.com/${GITHUB_REPOSITORY}/${IMAGE_NAME}:${IMAGE_TAG}"
diff --git a/.github/workflows/release.yaml b/.github/workflows/release.yaml
index 6aa9652..bf5c736 100644
--- a/.github/workflows/release.yaml
+++ b/.github/workflows/release.yaml
@@ -6,7 +6,8 @@ on:
       - v[0-9]+.[0-9]+.[0-9]+
 
 env:
-  IMAGE_NAME: notifier
+  DOCKER_REPO: ww24/calendar-notifier
+  IMAGE_NAME: calendar-notifier
 
 jobs:
   test:
@@ -14,16 +15,22 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v1
+      - uses: actions/cache@v2
+        with:
+          path: ~/go/pkg/mod
+          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+          restore-keys: |
+            ${{ runner.os }}-go-
       - uses: actions/setup-go@v1
         with:
-          go-version: "1.13"
+          go-version: "1.14"
       - name: setup env
         run: |
           echo "::set-env name=GOPATH::$(go env GOPATH)"
           echo "::add-path::$(go env GOPATH)/bin"
         shell: bash
       - name: Install go tools
-        run: cat tools.go | grep _ | awk -F '"' '{print $2}' | xargs -tI {} go install {}
+        run: cat tools.go | awk -F'"' '/_/ {print $2}' | xargs -tI {} go install {}
       - name: go generate
         run: go generate ./...
       - name: Check uncommitted changes
@@ -38,19 +45,13 @@ jobs:
       - run: go vet ./...
       - run: go test -v -race ./...
 
-  docker:
-    needs: test
-    name: Build and push docker image
+  docker_build_test:
+    name: Build docker image
     runs-on: ubuntu-latest
+    env:
+      IMAGE_TAG: latest
     steps:
       - uses: actions/checkout@v1
-      - name: Set image tag
-        run: |
-          tag=$(echo "${GITHUB_REF}" | sed "s/^refs\/tags\/v//")
-          if [ -z "$tag" ]; then
-            exit 1
-          fi
-          echo "::set-env name=IMAGE_TAG::$tag"
       - name: Shellcheck
         env:
           SHELLCHECK_OPTS: -e SC2187
@@ -73,7 +74,41 @@ jobs:
         run: |
           trivy -q --severity HIGH,CRITICAL --exit-code 1 \
             "docker.pkg.github.com/${GITHUB_REPOSITORY}/${IMAGE_NAME}:${IMAGE_TAG}"
-      - name: Push docker image
+
+  docker_push:
+    needs: [test, docker_build_test]
+    name: Build and push docker image
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v1
+      - uses: actions/cache@v2
+        with:
+          path: /tmp/.buildx-cache
+          key: ${{ runner.os }}-buildx-${{ github.sha }}
+          restore-keys: |
+            ${{ runner.os }}-buildx-
+      - name: Set image tag
+        run: |
+          tag=$(echo "${GITHUB_REF}" | sed "s/^refs\/tags\/v//")
+          if [ -z "$tag" ]; then
+            exit 1
+          fi
+          echo "::set-env name=IMAGE_TAG::$tag"
+      - name: Docker login
+        env:
+          DOCKER_USER: ${{ secrets.DOCKER_USER }}
+          DOCKER_PASSWORD: ${{ secrets.DOCKER_PASSWORD }}
+        run: echo "${DOCKER_PASSWORD}" | docker login --username "${DOCKER_USER}" --password-stdin
+      - name: Build docker image and push (DockerHub)
+        run: |
+          docker buildx build \
+            --cache-from "type=local,src=/tmp/.buildx-cache" \
+            --cache-to "type=local,dest=/tmp/.buildx-cache" \
+            --platform linux/amd64,linux/arm64,linux/arm/v7,linux/arm/v6 \
+            --output "type=image,push=true" \
+            -t "${DOCKER_REPO}":${IMAGE_TAG} .
+      - name: Push docker image (GitHub)
         run: |
+          docker build -t "docker.pkg.github.com/${GITHUB_REPOSITORY}/${IMAGE_NAME}:${IMAGE_TAG}" .
           echo "${{ secrets.GITHUB_TOKEN }}" | docker login -u owner --password-stdin docker.pkg.github.com
           docker push "docker.pkg.github.com/${GITHUB_REPOSITORY}/${IMAGE_NAME}:${IMAGE_TAG}"
diff --git a/README.md b/README.md
index d3b9a95..c3b6428 100644
--- a/README.md
+++ b/README.md
@@ -1,9 +1,11 @@
 calendar-notifier
 ===
 
-![](https://github.com/ww24/calendar-notifier/workflows/Test%20on%20master/badge.svg)
+![Test on master][github-actions-img]
 
-Calendar Notifier is Google Calendar event handler and actions.
+Calendar Notifier provides event handler and actions triggered by Google Calendar.
+
+[![dockeri.co][dockeri-img]][dockeri-url]
 
 ## Features
 
@@ -86,3 +88,7 @@ roles/pubsub.publisher
 
 #### References
 - https://cloud.google.com/pubsub/docs/access-control
+
+[github-actions-img]: https://github.com/ww24/calendar-notifier/workflows/Test%20on%20master/badge.svg?branch=master
+[dockeri-img]: https://dockeri.co/image/ww24/calendar-notifier
+[dockeri-url]: https://hub.docker.com/r/ww24/calendar-notifier