define GHA for CI
diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
new file mode 100644
index 0000000..760320e
--- /dev/null
+++ b/.github/workflows/ci.yaml
@@ -0,0 +1,106 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+#
+
+name: Continuous Integration
+
+on:
+  push:
+    branches: [ master ]
+    tags: [ '*' ]
+  pull_request:
+    branches: [ master ]
+    types: [ opened, synchronize, reopened ]
+  schedule:
+    - cron: '30 1 * * 1,3,5'
+
+permissions: read-all
+
+jobs:
+  ci:
+    runs-on: ubuntu-22.04
+    env:
+      PUSH_NIGHTLY: ${{ (github.event_name == 'push' || github.event_name == 'schedule') && github.ref == 'refs/heads/master' }}
+      PUSH_RELEASE: ${{ github.event_name == 'push' && github.ref_type == 'tag' }}
+    steps:
+      # Checkout just this repo and run scanCode before we do anything else
+      - name: Checkout runtime repo
+        uses: actions/checkout@v3
+        with:
+          path: runtime
+      - name: Scan Code
+        uses: apache/openwhisk-utilities/scancode@master
+
+      # Install core OpenWhisk artifacts needed to build/test anything else
+      - name: Checkout OpenWhisk core repo
+        uses: actions/checkout@v3
+        with:
+          repository: apache/openwhisk
+          path: core
+      - name: Setup Java
+        uses: actions/setup-java@v3
+        with:
+          distribution: 'temurin'
+          java-version: '11'
+      - name: Compile and Install Core OpenWhisk
+        working-directory: core
+        run: |
+          ./gradlew :tests:compileTestScala
+          ./gradlew install
+
+      # Build this repository
+      - name: Build Runtime
+        working-directory: runtime
+        run: |
+          ./gradlew distDocker
+
+      # Test this repository
+      - name: Test Runtime
+        working-directory: runtime
+        run: |
+          ./gradlew :tests:checkScalafmtAll
+          ./gradlew :tests:test
+
+      # Conditionally publish runtime images to DockerHub
+      # Important: naming convention for release tags is runtime@version
+      - name: Docker Login
+        if: ${{ env.PUSH_NIGHTLY  == 'true' || env.PUSH_RELEASE == 'true' }}
+        uses: docker/login-action@v2
+        with:
+          username: ${{ secrets.DOCKERHUB_USER_OPENWHISK }}
+          password: ${{ secrets.DOCKERHUB_TOKEN_OPENWHISK }}
+      - name: Push Nightly Images
+        if: ${{ env.PUSH_NIGHTLY  == 'true' }}
+        working-directory: runtime
+        run: |
+          SHORT_COMMIT=$(git rev-parse --short "$GITHUB_SHA")
+          ./gradlew :core:ruby2.5Action:distDocker -PdockerRegistry=docker.io -PdockerImagePrefix=openwhisk -PdockerImageTag=nightly
+          ./gradlew :core:ruby2.5Action:distDocker -PdockerRegistry=docker.io -PdockerImagePrefix=openwhisk -PdockerImageTag=$SHORT_COMMIT
+          ./gradlew :core:ruby2.6ActionLoop:distDocker -PdockerRegistry=docker.io -PdockerImagePrefix=openwhisk -PdockerImageTag=nightly
+          ./gradlew :core:ruby2.6ActionLoop:distDocker -PdockerRegistry=docker.io -PdockerImagePrefix=openwhisk -PdockerImageTag=$SHORT_COMMIT
+      - name: Push Release Images
+        if: ${{ env.PUSH_RELEASE == 'true' }}
+        working-directory: runtime
+        run: |
+          RUNTIME_VERSION=${GITHUB_REF_NAME%@*}
+          IMAGE_TAG=${GITHUB_REF_NAME##*@}
+          if [ ${RUNTIME_VERSION} == "2.5" ]; then
+            RUNTIME="ruby2.5Action"
+          elif [ ${RUNTIME_VERSION} == "2.6" ]; then
+            RUNTIME="ruby2.6ActionLoop"
+          fi
+          ./gradlew :core:$RUNTIME:distDocker -PdockerRegistry=docker.io -PdockerImagePrefix=openwhisk -PdockerImageTag=$IMAGE_TAG