diff --git a/.github/workflows/build-debug.yml b/.github/workflows/build-debug.yml
index c558169..d409df8 100644
--- a/.github/workflows/build-debug.yml
+++ b/.github/workflows/build-debug.yml
@@ -21,6 +21,10 @@ jobs:
       NUGET_XMLDOC_MODE: skip
     steps:
       - uses: actions/checkout@v2
+      - uses: actions/setup-dotnet@v1
+        with:
+          dotnet-version: ${{ env.DOTNET_SDK_VERSION }}
+          include-prerelease: ${{ env.DOTNET_INCLUDE_PRERELEASE }}
       - run: dotnet build -c Debug
       - run: dotnet test -c Debug --no-build < /dev/null
 
@@ -28,10 +32,10 @@ jobs:
     if: "((github.event_name == 'push' && github.repository_owner == 'Cysharp') || startsWith(github.event.pull_request.head.label, 'Cysharp:'))"
     strategy:
       matrix:
-        unity: ["2020.1.0a3"]
+        unity: ["2019.4.25f1"]
         include:
-          - unity: 2020.1.0a3
-            license: UNITY_LICENSE_2020
+          - unity: 2019.4.25f1
+            license: UNITY_LICENSE_2019
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2