diff --git a/.github/workflows/build_tests.yml b/.github/workflows/build_tests.yml
index 0a68c899643..fd43aae0565 100644
--- a/.github/workflows/build_tests.yml
+++ b/.github/workflows/build_tests.yml
@@ -21,18 +21,44 @@ jobs:
       ENABLE_CACHING: false
     steps:
       - uses: actions/checkout@v2
-      - name: Clone Oppia Bazel
-        run: git clone https://github.com/oppia/bazel.git $HOME/oppia-bazel
+
       - name: Set up JDK 9
         uses: actions/setup-java@v1
         with:
           java-version: 9
-      - name: Extract Android tools
+
+      - name: Check Java version & path
+        run: |
+          which java
+          java -version
+          echo "Java home: $JAVA_HOME"
+          $JAVA_HOME/bin/java -version
+
+      - name: Set up Bazel
+        uses: abhinavsingh/setup-bazel@v3
+        with:
+          version: 4.0.0
+
+      - name: Configure Bazel to use JDK 9 for building
+        run: |
+          echo "build --java_language_version=9" >> $HOME/.bazelrc
+
+      - name: Configure Bazel to use specific sandbox tmpfs
+        run: |
+          echo "build --enable_platform_specific_config" >> $HOME/.bazelrc
+          echo "build:linux --sandbox_tmpfs_path=/tmp" >> $HOME/.bazelrc
+          
+      - name: Check Bazel environment
+        run: bazel info
+
+      - name: Set up Oppia Bazel Android Tools
         run: |
-          mkdir -p $GITHUB_WORKSPACE/tmp/android_tools
-          cd $HOME/oppia-bazel
-          unzip bazel-tools.zip
-          tar -xf $HOME/oppia-bazel/android_tools.tar.gz -C $GITHUB_WORKSPACE/tmp/android_tools
+          mkdir $HOME/opensource
+          cd $HOME/opensource
+          git clone https://github.com/oppia/oppia-bazel-tools
+          echo build --override_repository=android_tools="$(cd "$(dirname "$HOME/opensource/oppia-bazel-tools")"; pwd)/$(basename "$HOME/opensource/oppia-bazel-tools")" >> $HOME/.bazelrc
+          echo build --android_databinding_use_androidx >> $HOME/.bazelrc
+
       # See https://git-secret.io/installation for details on installing git-secret. Note that the
       # apt-get method isn't used since it's much slower to update & upgrade apt before installation
       # versus just directly cloning & installing the project. Further, the specific version
@@ -50,6 +76,7 @@ jobs:
           PREFIX="$HOME/gitsecret" make install
           echo "$HOME/gitsecret" >> $GITHUB_PATH
           echo "$HOME/gitsecret/bin" >> $GITHUB_PATH
+
       - name: Decrypt secrets (non-fork only)
         if: ${{ env.ENABLE_CACHING == 'true' && github.event.pull_request.head.repo.full_name == 'oppia/oppia-android' }}
         env:
@@ -61,25 +88,23 @@ jobs:
           gpg --import ./git_secret_private_key.gpg
           cd $GITHUB_WORKSPACE
           git secret reveal
-      - name: Unzip Bazel binary
-        run: |
-          cd $HOME/oppia-bazel
-          unzip bazel-build.zip
-          cd $GITHUB_WORKSPACE
-          chmod a+x $HOME/oppia-bazel/bazel
+
       # Note that caching only works on non-forks.
       - name: Build Oppia binary (with caching, non-fork only)
         if: ${{ env.ENABLE_CACHING == 'true' && github.event.pull_request.head.repo.full_name == 'oppia/oppia-android' }}
         env:
           BAZEL_REMOTE_CACHE_URL: ${{ secrets.BAZEL_REMOTE_CACHE_URL }}
         run: |
-          $HOME/oppia-bazel/bazel build --override_repository=android_tools=$GITHUB_WORKSPACE/tmp/android_tools --remote_http_cache=$BAZEL_REMOTE_CACHE_URL --google_credentials=./config/oppia-dev-workflow-remote-cache-credentials.json -- //:oppia
+          bazel build --remote_http_cache=$BAZEL_REMOTE_CACHE_URL --google_credentials=./config/oppia-dev-workflow-remote-cache-credentials.json -- //:oppia
+
       - name: Build Oppia binary (without caching, or on a fork)
         if: ${{ env.ENABLE_CACHING == 'false' || github.event.pull_request.head.repo.full_name != 'oppia/oppia-android' }}
         run: |
-          $HOME/oppia-bazel/bazel build --override_repository=android_tools=$GITHUB_WORKSPACE/tmp/android_tools -- //:oppia
+          bazel build -- //:oppia
+
       - name: Copy Oppia APK for uploading
         run: cp $GITHUB_WORKSPACE/bazel-bin/oppia.apk /home/runner/work/oppia-android/oppia-android/
+
       - uses: actions/upload-artifact@v2
         with:
           name: oppia-bazel-apk
diff --git a/.github/workflows/unit_tests.yml b/.github/workflows/unit_tests.yml
index 82295e047a8..84a48991ed2 100644
--- a/.github/workflows/unit_tests.yml
+++ b/.github/workflows/unit_tests.yml
@@ -65,14 +65,36 @@ jobs:
       ENABLE_CACHING: false
     steps:
       - uses: actions/checkout@v2
+
       - name: Set up JDK 9
         uses: actions/setup-java@v1
         with:
           java-version: 9
+
+      - name: Check Java version & path
+        run: |
+          which java
+          java -version
+          echo "Java home: $JAVA_HOME"
+          $JAVA_HOME/bin/java -version
+
       - name: Set up Bazel
         uses: abhinavsingh/setup-bazel@v3
         with:
           version: 4.0.0
+          
+      - name: Configure Bazel to use JDK 9 for building
+        run: |
+          echo "build --java_language_version=9" >> $HOME/.bazelrc
+
+      - name: Configure Bazel to use specific sandbox tmpfs
+        run: |
+          echo "build --enable_platform_specific_config" >> $HOME/.bazelrc
+          echo "build:linux --sandbox_tmpfs_path=/tmp" >> $HOME/.bazelrc
+
+      - name: Check Bazel environment
+        run: bazel info
+
       - name: Set up Oppia Bazel Android Tools
         run: |
           mkdir $HOME/opensource
@@ -80,6 +102,7 @@ jobs:
           git clone https://github.com/oppia/oppia-bazel-tools
           echo build --override_repository=android_tools="$(cd "$(dirname "$HOME/opensource/oppia-bazel-tools")"; pwd)/$(basename "$HOME/opensource/oppia-bazel-tools")" >> $HOME/.bazelrc
           echo build --android_databinding_use_androidx >> $HOME/.bazelrc
+
       # See explanation in bazel_build_app for how this is installed.
       - name: Install git-secret (non-fork only)
         if: ${{ env.ENABLE_CACHING == 'true' && ((github.ref == 'refs/heads/develop' && github.event_name == 'push') || (github.event.pull_request.head.repo.full_name == 'oppia/oppia-android')) }}
@@ -92,6 +115,7 @@ jobs:
           PREFIX="$HOME/gitsecret" make install
           echo "$HOME/gitsecret" >> $GITHUB_PATH
           echo "$HOME/gitsecret/bin" >> $GITHUB_PATH
+
       - name: Decrypt secrets (non-fork only)
         if: ${{ env.ENABLE_CACHING == 'true' && ((github.ref == 'refs/heads/develop' && github.event_name == 'push') || (github.event.pull_request.head.repo.full_name == 'oppia/oppia-android')) }}
         env:
@@ -103,11 +127,13 @@ jobs:
           gpg --import ./git_secret_private_key.gpg
           cd $GITHUB_WORKSPACE
           git secret reveal
+
       - name: Run Oppia Test (with caching, non-fork only)
         if: ${{ env.ENABLE_CACHING == 'true' && ((github.ref == 'refs/heads/develop' && github.event_name == 'push') || (github.event.pull_request.head.repo.full_name == 'oppia/oppia-android')) }}
         env:
           BAZEL_REMOTE_CACHE_URL: ${{ secrets.BAZEL_REMOTE_CACHE_URL }}
         run: bazel test --remote_http_cache=$BAZEL_REMOTE_CACHE_URL --google_credentials=./config/oppia-dev-workflow-remote-cache-credentials.json -- ${{ matrix.test-target }}
+
       - name: Run Oppia Test (without caching, or on a fork)
         if: ${{ env.ENABLE_CACHING == 'false' || ((github.ref != 'refs/heads/develop' || github.event_name != 'push') && (github.event.pull_request.head.repo.full_name != 'oppia/oppia-android')) }}
         env: