diff --git a/.circleci/config.yml b/.circleci/config.yml
deleted file mode 100644
index 58ead3b..0000000
--- a/.circleci/config.yml
+++ /dev/null
@@ -1,114 +0,0 @@
-version: 2.1
-executors:
-  unity:
-    # https://hub.docker.com/r/gableroux/unity3d/tags
-    parameters:
-      version: {type: string}
-    docker:
-      - image: gableroux/unity3d:<< parameters.version >>
-  go:
-    docker:
-      - image: circleci/golang      
-commands:
-  unity_activate:
-    parameters:
-      unity_version: {type: string}
-      unity_license: {type: string}
-    steps:
-      # get activation file, if fail to activate unity, use this key and activate from https://license.unity3d.com/manual
-      - run: apt update && apt install libunwind8 -y
-      - run: /opt/Unity/Editor/Unity -quit -batchmode -nographics -logFile -createManualActivationFile || exit 0
-      - run: cat Unity_v<< parameters.unity_version >>.alf
-      # get from UNITY_LICENSE envvar(base64 encoded(cat foo.ulf | base64 )), this file is generated from above manual activation
-      - run: echo << parameters.unity_license >> | base64 -di  >> .circleci/Unity.ulf
-      - run: /opt/Unity/Editor/Unity -quit -batchmode -nographics -silent-crashes -logFile -manualLicenseFile .circleci/Unity.ulf || exit 0
-jobs:
-  build-and-test:
-    parameters:
-      unity_version: {type: string}
-      unity_license: {type: string}
-    executor:
-      name: unity
-      version: << parameters.unity_version >>
-    steps:
-      - checkout
-      - unity_activate:
-          unity_version: << parameters.unity_version >>
-          unity_license: << parameters.unity_license >>
-      - run:
-          name: Build Linux(Mono)
-          command: /opt/Unity/Editor/Unity -quit -batchmode -nographics -silent-crashes -logFile -projectPath . -executeMethod UnitTestBuilder.BuildUnitTest /headless /ScriptBackend Mono2x /BuildTarget StandaloneLinux64
-          working_directory: .
-      # TODO:check unity version and packages...
-      # - run: ./bin/UnitTest/StandaloneLinux64_Mono2x/test
-  build-and-create-package:
-    parameters:
-      unity_version: {type: string}
-      unity_license: {type: string}
-    executor:
-      name: unity
-      version: << parameters.unity_version >>
-    steps:
-      - checkout
-      - unity_activate:
-          unity_version: << parameters.unity_version >>
-          unity_license: << parameters.unity_license >>
-      - run:
-          name: Export unitypackage
-          command: /opt/Unity/Editor/Unity -quit -batchmode -nographics -silent-crashes -logFile -projectPath . -executeMethod PackageExporter.Export
-          working_directory: .
-      - store_artifacts:
-          path: ./UniRx.Async.unitypackage
-          destination: /UniRx.Async.unitypackage
-  # upload to github by ghr
-  upload-github:
-    executor: go
-    steps:
-      - attach_workspace:
-          at: .
-      - run: go get github.com/tcnksm/ghr
-      - run: ghr -t ${GITHUB_TOKEN} -u ${CIRCLE_PROJECT_USERNAME} -r ${CIRCLE_PROJECT_REPONAME} ${CIRCLE_TAG} .
-      - store_artifacts:
-          path: UniRx.Async.unitypackage
-          destination: UniRx.Async.unitypackage          
-workflows:
-  version: 2
-  build-unity:
-    jobs:
-      # does not exists yet.
-      # - build-and-test:
-      #     unity_version: 2019.3.0a2
-      #     unity_license: ${UNITY_LICENSE_2019_3}
-      # - build-and-test:
-      #     unity_version: 2019.2.0b2
-      #     unity_license: ${UNITY_LICENSE_2019_2}
-      - build-and-test:
-          unity_version: 2019.1.2f1
-          unity_license: ${UNITY_LICENSE_2019_1}
-          filters:
-            tags:
-              only: /.*/
-      # test asmdef will not found.
-      # - build-and-test:
-      #     unity_version: 2018.4.0f1
-      #     unity_license: ${UNITY_LICENSE_2018_4}
-      # # UniTask minimum support version is 2018.3(C# 7.x)
-      # - build-and-test:
-      #     unity_version: 2018.3.12f1
-      #     unity_license: ${UNITY_LICENSE_2018_3}
-      - build-and-create-package:
-          unity_version: 2019.1.2f1
-          unity_license: ${UNITY_LICENSE_2019_1}
-          filters:
-            tags:
-              only: /^\d\.\d\.\d.*/
-            branches:
-              ignore: /.*/
-      - upload-github:
-          requires:
-            - build-and-create-package
-          filters:
-            tags:
-              only: /^\d\.\d\.\d.*/
-            branches:
-              ignore: /.*/
diff --git a/.github/workflows/build-debug.yml b/.github/workflows/build-debug.yml
new file mode 100644
index 0000000..1a9a4b5
--- /dev/null
+++ b/.github/workflows/build-debug.yml
@@ -0,0 +1,73 @@
+name: Build-Debug
+
+on:
+  push:
+    branches:
+      - "**"
+    tags:
+      - "!*" # not a tag push
+  pull_request:
+    types:
+      - opened
+      - synchronize
+
+jobs:
+  build-dotnet:
+    runs-on: ubuntu-latest
+    env:
+      DOTNET_CLI_TELEMETRY_OPTOUT: 1
+      DOTNET_SKIP_FIRST_TIME_EXPERIENCE: 1
+      NUGET_XMLDOC_MODE: skip
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-dotnet@v1
+        with:
+          dotnet-version: 3.1.101
+      - run: dotnet test -c Debug ./src/UniTask.NetCoreTests/UniTask.NetCoreTests.csproj
+
+  build-unity:
+    strategy:
+      matrix:
+        unity: ['2019.3.9f1', '2020.1.0b5']
+        include:
+          - unity: 2019.3.9f1
+            license: UNITY_2019_3
+          - unity: 2020.1.0b5
+            license: UNITY_2020_1
+    runs-on: ubuntu-latest
+    container:
+      # with linux-il2cpp. image from https://hub.docker.com/r/gableroux/unity3d/tags
+      image: gableroux/unity3d:${{ matrix.unity }}-linux-il2cpp
+    steps:
+      - run: apt update && apt install git -y
+      - uses: actions/checkout@v2
+      # create unity activation file and store to artifacts.
+      - run: /opt/Unity/Editor/Unity -quit -batchmode -nographics -logFile -createManualActivationFile || exit 0
+      - uses: actions/upload-artifact@v1
+        with:
+          name: Unity_v${{ matrix.unity }}.alf
+          path: ./Unity_v${{ matrix.unity }}.alf
+      # activate Unity from manual license file(ulf)
+      - run: echo -n "$UNITY_LICENSE" >> .Unity.ulf
+        env:
+          UNITY_LICENSE: ${{ secrets[matrix.license] }}
+      - name: Activate Unity, always returns a success. But if a subsequent run fails, the activation may have failed(if succeeded, shows `Next license update check is after` and not shows other message(like GUID != GUID). If fails not). In that case, upload the artifact's .alf file to https://license.unity3d.com/manual to get the .ulf file and set it to secrets.
+        run: /opt/Unity/Editor/Unity -quit -batchmode -nographics -silent-crashes -logFile -manualLicenseFile .Unity.ulf || exit 0
+
+      # Execute scripts: RuntimeUnitTestToolkit
+      - name: Build UnitTest(Linux64, mono)
+        run: /opt/Unity/Editor/Unity -quit -batchmode -nographics -silent-crashes -logFile -projectPath . -executeMethod UnitTestBuilder.BuildUnitTest /headless /ScriptBackend mono /BuildTarget StandaloneLinux64
+        working-directory: src/UniTask
+      - name: Execute UnitTest
+        run: ./src/UniTask/bin/UnitTest/StandaloneLinux64_Mono2x/test
+
+      # Execute scripts: Export Package
+      - name: Export unitypackage
+        run: /opt/Unity/Editor/Unity -quit -batchmode -nographics -silent-crashes -logFile -projectPath . -executeMethod PackageExporter.Export
+        working-directory: src/UniTask
+
+      # Store artifacts.      
+      - uses: actions/upload-artifact@v2
+        with:
+          name: UniTask.unitypackage
+          path: ./src/UniTask/*.unitypackage
\ No newline at end of file
diff --git a/.github/workflows/build-release.yml b/.github/workflows/build-release.yml
new file mode 100644
index 0000000..9b8844b
--- /dev/null
+++ b/.github/workflows/build-release.yml
@@ -0,0 +1,108 @@
+name: Build-Release
+
+on:
+  push:
+    tags:
+      - "[0-9]+.[0-9]+.[0-9]+*"
+
+jobs:
+  build-dotnet:
+    runs-on: ubuntu-latest
+    env:
+      DOTNET_CLI_TELEMETRY_OPTOUT: 1
+      DOTNET_SKIP_FIRST_TIME_EXPERIENCE: 1
+      NUGET_XMLDOC_MODE: skip
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-dotnet@v1
+        with:
+          dotnet-version: 3.1.101
+      # set release tag(*.*.*) to env.GIT_TAG
+      - run: echo ::set-env name=GIT_TAG::${GITHUB_REF#refs/tags/}
+
+      # build CommandTools first (use dotnet run command in ZLogger.csproj)
+      - run: dotnet build -c Release ./tools/CommandTools/CommandTools.csproj
+      - run: dotnet build -c Release -p:Version=${{ env.GIT_TAG }}
+      - run: dotnet test -c Release --no-build
+      - run: dotnet pack ./src/ZLogger/ZLogger.csproj -c Release --no-build -p:Version=${{ env.GIT_TAG }}
+
+      # Store artifacts.
+      - uses: actions/upload-artifact@v1
+        with:
+          name: nuget
+          path: ./src/ZLogger/bin/Release/ZLogger.${{ env.GIT_TAG }}.nupkg
+      
+  build-unity:
+    strategy:
+      matrix:
+        unity: ['2019.3.9f1']
+        include:
+          - unity: 2019.3.9f1
+            license: UNITY_2019_3
+    runs-on: ubuntu-latest
+    container:
+      # with linux-il2cpp. image from https://hub.docker.com/r/gableroux/unity3d/tags
+      image: gableroux/unity3d:${{ matrix.unity }}-linux-il2cpp
+    steps:
+      - run: apt update && apt install git -y
+      - uses: actions/checkout@v2
+      - run: echo -n "$UNITY_LICENSE" >> .Unity.ulf
+        env:
+          UNITY_LICENSE: ${{ secrets[matrix.license] }}
+      - run: /opt/Unity/Editor/Unity -quit -batchmode -nographics -silent-crashes -logFile -manualLicenseFile .Unity.ulf || exit 0
+
+      # set release tag(*.*.*) to env.GIT_TAG
+      - run: echo ::set-env name=GIT_TAG::${GITHUB_REF#refs/tags/}
+
+      # Execute scripts: Export Package
+      - name: Export unitypackage
+        run: /opt/Unity/Editor/Unity -quit -batchmode -nographics -silent-crashes -logFile -projectPath . -executeMethod PackageExporter.Export
+        working-directory: src/ZLogger.Unity
+        env:
+          UNITY_PACKAGE_VERSION: ${{ env.GIT_TAG }}
+
+      # Store artifacts.
+      - uses: actions/upload-artifact@v1
+        with:
+          name: ZLogger.Unity.${{ env.GIT_TAG }}.unitypackage
+          path: ./src/ZLogger.Unity/ZLogger.Unity.${{ env.GIT_TAG }}.unitypackage
+
+  create-release:
+    needs: [build-dotnet, build-unity]
+    runs-on: ubuntu-latest
+    env:
+      DOTNET_CLI_TELEMETRY_OPTOUT: 1
+      DOTNET_SKIP_FIRST_TIME_EXPERIENCE: 1
+      NUGET_XMLDOC_MODE: skip
+    steps:
+    # setup dotnet for nuget push
+    - uses: actions/setup-dotnet@v1
+      with:
+        dotnet-version: 3.1.101
+    # set release tag(*.*.*) to env.GIT_TAG
+    - run: echo ::set-env name=GIT_TAG::${GITHUB_REF#refs/tags/}
+
+    # Create Releases
+    - uses: actions/create-release@v1
+      id: create_release
+      env:
+        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      with:
+        tag_name: ${{ github.ref }}
+        release_name: Ver.${{ github.ref }}
+
+    # Download (All) Artifacts to current directory
+    - uses: actions/download-artifact@v2-preview
+
+    # Upload to NuGet
+    - run: dotnet nuget push "./nuget/*.nupkg" -s https://www.nuget.org/api/v2/package -k ${{ secrets.NUGET_KEY }}
+
+    # Upload to Releases(unitypackage)
+    - uses: actions/upload-release-asset@v1
+      env:
+        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      with:
+        upload_url: ${{ steps.create_release.outputs.upload_url }}
+        asset_path: ./ZLogger.Unity.${{ env.GIT_TAG }}.unitypackage/ZLogger.Unity.${{ env.GIT_TAG }}.unitypackage
+        asset_name: ZLogger.Unity.${{ env.GIT_TAG }}.unitypackage
+        asset_content_type: application/octet-stream
\ No newline at end of file
diff --git a/.github/workflows/toc.yml b/.github/workflows/toc.yml
new file mode 100644
index 0000000..f7519c3
--- /dev/null
+++ b/.github/workflows/toc.yml
@@ -0,0 +1,15 @@
+name: TOC Generator
+
+on:
+  push:
+    paths:
+      - 'README.md'
+
+jobs:
+  generateTOC:
+    name: TOC Generator
+    runs-on: ubuntu-latest
+    steps:
+      - uses: technote-space/toc-generator@v2.4.0
+        with:
+          TOC_TITLE: "## Table of Contents"
\ No newline at end of file