diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index d228a39..ec96131 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -4,36 +4,49 @@ on:
   push:
   workflow_dispatch:
 
+# No marketplace actions: this Gitea runner resolves bare action names
+# against the local instance, and even with full URLs it cannot resolve
+# annotated tags ("unsupported object type"). Everything below is plain
+# shell, which also keeps the job readable.
 jobs:
   build:
     runs-on: ubuntu-latest
+    env:
+      ANDROID_SDK_ROOT: /opt/android-sdk
+      CMDLINE_TOOLS: https://dl.google.com/android/repository/commandlinetools-linux-11076708_latest.zip
     steps:
-      # Full URLs: this Gitea resolves bare action names against itself,
-      # where these actions do not exist.
-      - uses: https://github.com/actions/checkout@v4
+      - name: Checkout
+        run: |
+          git init -q .
+          git remote add origin "${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY}.git"
+          git fetch -q --depth 1 origin "${GITHUB_SHA}"
+          git checkout -q FETCH_HEAD
 
-      - uses: https://github.com/actions/setup-java@v4
-        with:
-          distribution: temurin
-          java-version: "17"
+      - name: Install JDK
+        run: |
+          apt-get update -qq
+          DEBIAN_FRONTEND=noninteractive apt-get install -y -qq openjdk-17-jdk-headless > /dev/null
+          java -version
 
-      - uses: https://github.com/gradle/actions/setup-gradle@v4
+      - name: Install Android SDK
+        run: |
+          mkdir -p "$ANDROID_SDK_ROOT/cmdline-tools"
+          curl -sSL -o /tmp/tools.zip "$CMDLINE_TOOLS"
+          unzip -q /tmp/tools.zip -d "$ANDROID_SDK_ROOT/cmdline-tools"
+          mv "$ANDROID_SDK_ROOT/cmdline-tools/cmdline-tools" "$ANDROID_SDK_ROOT/cmdline-tools/latest"
+          yes | "$ANDROID_SDK_ROOT/cmdline-tools/latest/bin/sdkmanager" --licenses > /dev/null
+          "$ANDROID_SDK_ROOT/cmdline-tools/latest/bin/sdkmanager" \
+            "platforms;android-35" "build-tools;35.0.0" "platform-tools" > /dev/null
+          echo "sdk.dir=$ANDROID_SDK_ROOT" > local.properties
 
       - name: Unit tests
-        run: ./gradlew testDebugUnitTest --stacktrace
+        run: ./gradlew testDebugUnitTest --no-daemon --stacktrace
 
       - name: Build debug APK
-        run: ./gradlew assembleDebug --stacktrace
+        run: ./gradlew assembleDebug --no-daemon --stacktrace
 
-      - name: Upload APK
-        uses: https://github.com/actions/upload-artifact@v4
-        with:
-          name: castarr-debug-apk
-          path: app/build/outputs/apk/debug/app-debug.apk
-
-      - name: Upload test report
+      - name: Summary
         if: always()
-        uses: https://github.com/actions/upload-artifact@v4
-        with:
-          name: castarr-test-report
-          path: tests/runs/
+        run: |
+          echo "APK:"; ls -la app/build/outputs/apk/debug/ 2>/dev/null || echo "  (kein Build)"
+          echo "Tests:"; ls tests/runs/junit/ 2>/dev/null || echo "  (keine Reports)"