diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index 9ae0a8392f94..852b940228fb 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -57,7 +57,7 @@ jobs:
         TEST_ALL_PACKAGES: ${{ steps.check-label.outputs.is_full_run }}
       run: |
         if [ -n "$TARGET_BRANCH" ]; then
-          git fetch origin "$TARGET_BRANCH" --deepen=200 || true
+          git fetch --no-tags --quiet origin "$TARGET_BRANCH" --deepen=200 || true
         fi
         python3 ci/get_package_shards.py
 
diff --git a/.github/workflows/unittest.yml b/.github/workflows/unittest.yml
index 0b5df0687e57..89df3022e2b3 100644
--- a/.github/workflows/unittest.yml
+++ b/.github/workflows/unittest.yml
@@ -74,7 +74,7 @@ jobs:
         PACKAGE_WEIGHTS: ${{ env.PACKAGE_WEIGHTS }}
       run: |
         if [ -n "$TARGET_BRANCH" ]; then
-          git fetch origin "$TARGET_BRANCH" --depth=1 || true
+          git fetch --no-tags --quiet origin "$TARGET_BRANCH" --depth=1 || true
         fi
         python3 ci/get_package_shards.py
 
diff --git a/ci/run_conditional_tests.sh b/ci/run_conditional_tests.sh
index 36f2af877db7..34f401aaa22f 100755
--- a/ci/run_conditional_tests.sh
+++ b/ci/run_conditional_tests.sh
@@ -55,9 +55,9 @@ elif [[ ${BUILD_TYPE} == "presubmit" ]]; then
     # common commit in the target branch.
     if [ -n "${TARGET_BRANCH}" ]; then
         if [[ "${TEST_TYPE}" == "import_profile" ]]; then
-            git fetch origin "${TARGET_BRANCH}:refs/remotes/origin/${TARGET_BRANCH}" || true
+            git fetch --no-tags --quiet origin "${TARGET_BRANCH}:refs/remotes/origin/${TARGET_BRANCH}" || true
         else
-            git fetch origin "${TARGET_BRANCH}:refs/remotes/origin/${TARGET_BRANCH}" --depth=200 || true
+            git fetch --no-tags --quiet origin "${TARGET_BRANCH}:refs/remotes/origin/${TARGET_BRANCH}" --depth=200 || true
         fi
     fi
     GIT_DIFF_ARG="origin/${TARGET_BRANCH}..."
@@ -78,21 +78,34 @@ run_test_in_dir() {
     local log_file="/tmp/test_log_${PY_VERSION}_${pkg_name_clean}.log"
     export COVERAGE_FILE="${PROJECT_ROOT}/.coverage.${PY_VERSION}.${pkg_name_clean}"
 
+    echo "============================================================"
+    echo "Starting tests in ${d}"
+    echo "============================================================"
+
     pushd ${d} > /dev/null
     set +e
-    ${test_script} > "${log_file}" 2>&1
-    local ret=$?
+    if [ "${PARALLEL_WORKERS}" = "1" ]; then
+        # When running with a single worker, stream output in real-time while capturing to log file
+        ${test_script} 2>&1 | tee "${log_file}"
+        local ret=${PIPESTATUS[0]}
+    else
+        # When running multiple workers in parallel, buffer output to prevent interleaved log lines
+        ${test_script} > "${log_file}" 2>&1
+        local ret=$?
+        echo "============================================================"
+        echo "Finished tests in ${d} (exit code: ${ret})"
+        echo "============================================================"
+        cat "${log_file}"
+    fi
     set -e
     popd > /dev/null
-
-    echo "============================================================"
-    echo "Running tests in ${d}"
-    echo "============================================================"
-    cat "${log_file}"
     rm -f "${log_file}"
 
     if [ ${ret} -ne 0 ]; then
-        exit ${ret}
+        echo "❌ Tests failed in ${d} with exit code ${ret}"
+        exit 255  # Cancel xargs parallel jobs
+    else
+        echo "✅ Tests passed in ${d}"
     fi
 }
 export -f run_test_in_dir
diff --git a/ci/run_single_test.sh b/ci/run_single_test.sh
index 514cc5c2b16e..0ea0b969770d 100755
--- a/ci/run_single_test.sh
+++ b/ci/run_single_test.sh
@@ -71,28 +71,28 @@ case ${TEST_TYPE} in
     unit)
         case ${PY_VERSION} in
         "3.10")
-            nox -s unit-3.10
+            nox --stop-on-first-error -s unit-3.10
             retval=$?
             ;;
         "3.11")
-            nox -s unit-3.11
+            nox --stop-on-first-error -s unit-3.11
             retval=$?
             ;;
         "3.12")
-            nox -s unit-3.12
+            nox --stop-on-first-error -s unit-3.12
             retval=$?
             ;;
         "3.13")
-            nox -s unit-3.13
+            nox --stop-on-first-error -s unit-3.13
             retval=$?
             ;;
         "3.14")
-            nox -s unit-3.14
+            nox --stop-on-first-error -s unit-3.14
             retval=$?
             ;;
         "3.15")
             # This is needed to speed up builds
-            nox --force-venv-backend uv -s unit-3.15
+            nox --stop-on-first-error --force-venv-backend uv -s unit-3.15
             retval=$?
             ;;
         *)
@@ -212,7 +212,7 @@ case ${TEST_TYPE} in
         fi
         ;;
     *)
-        nox -s ${TEST_TYPE}
+        nox --stop-on-first-error -s ${TEST_TYPE}
         retval=$?
         ;;
     esac