diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index dcfee90a4f3e..19f44acf2584 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -23,8 +23,8 @@ on:
   pull_request:
 name: ci
 jobs:
-  # detect whether or note we should run "bulk" (non-handwritten) unit tests
-  bulk-filter:
+  # detect whether or not we should run generated (non-handwritten) unit tests
+  generated-libraries-filter:
     runs-on: ubuntu-latest
     permissions:
       pull-requests: read
@@ -57,10 +57,11 @@ jobs:
           ci:
             - '.github/workflows/ci.yaml'
             - '.kokoro/**'
-  # these unit tests are "bulk" (non-handwritten) libraries
+  # compile all modules across supported Java versions
   units:
     runs-on: ubuntu-latest
-    needs: bulk-filter
+    needs: generated-libraries-filter
+    if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' }}
     strategy:
       fail-fast: false
       matrix:
@@ -68,76 +69,71 @@ jobs:
     steps:
     - name: Get current week within the year
       id: date
-      if: ${{ needs.bulk-filter.outputs.runnable == 'true' }}
+      if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' }}
       run: echo "::set-output name=week_of_year::$(date +'%W' --utc)"
     - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
-      if: ${{ needs.bulk-filter.outputs.runnable == 'true' }}
+      if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' }}
       with:
         persist-credentials: false
     - uses: actions/setup-java@c1e323688fd81a25caa38c78aa6df2d33d3e20d9 # v4.8.0
-      if: ${{ needs.bulk-filter.outputs.runnable == 'true' }}
+      if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' }}
       with:
         distribution: temurin
         java-version: ${{matrix.java}}
     - run: java -version
-      if: ${{ needs.bulk-filter.outputs.runnable == 'true' }}
+      if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' }}
     - uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830 # v4
       id: mvn-cache
-      if: ${{ needs.bulk-filter.outputs.runnable == 'true' }}
+      if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' }}
       with:
         path: ~/.m2/repository
         key: ${{ runner.os }}-maven-unified-${{ steps.date.outputs.week_of_year }}
     - run: .kokoro/build.sh
-      if: ${{ needs.bulk-filter.outputs.runnable == 'true' && (needs.bulk-filter.outputs.src == 'true' || needs.bulk-filter.outputs.ci == 'true') }}
+      if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' && (needs.generated-libraries-filter.outputs.src == 'true' || needs.generated-libraries-filter.outputs.ci == 'true') }}
       env:
         JOB_TYPE: test
         JOB_NAME: units-${{matrix.java}}
   units-8-runtime:
     runs-on: ubuntu-latest
-    needs: bulk-filter
+    needs: generated-libraries-filter
+    if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' }}
     name: "units (8)"
     steps:
     - name: Get current week within the year
       id: date
-      if: ${{ needs.bulk-filter.outputs.runnable == 'true' }}
+      if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' }}
       run: echo "::set-output name=week_of_year::$(date +'%W' --utc)"
     - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
-      if: ${{ needs.bulk-filter.outputs.runnable == 'true' }}
+      if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' }}
       with:
         persist-credentials: false
     - uses: actions/setup-java@c1e323688fd81a25caa38c78aa6df2d33d3e20d9 # v4.8.0
-      if: ${{ needs.bulk-filter.outputs.runnable == 'true' }}
+      if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' }}
       with:
         java-version: 8
         distribution: temurin
-    - name: "Set jvm system property environment variable for surefire plugin (unit tests)"
-      # Maven surefire plugin (unit tests) allows us to specify JVM to run the tests.
-      # https://maven.apache.org/surefire/maven-surefire-plugin/test-mojo.html#jvm
-      if: ${{ needs.bulk-filter.outputs.runnable == 'true' }}
-      run: echo "SUREFIRE_JVM_OPT=-Djvm=${JAVA_HOME}/bin/java" >> $GITHUB_ENV
-      shell: bash    
     - uses: actions/setup-java@c1e323688fd81a25caa38c78aa6df2d33d3e20d9 # v4.8.0
-      if: ${{ needs.bulk-filter.outputs.runnable == 'true' }}
+      if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' }}
       with:
         java-version: 11
         distribution: temurin
         cache: maven
     - uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830 # v4
       id: mvn-cache
-      if: ${{ needs.bulk-filter.outputs.runnable == 'true' }}
+      if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' }}
       with:
         path: ~/.m2/repository
         key: ${{ runner.os }}-maven-unified-${{ steps.date.outputs.week_of_year }}
     - run: .kokoro/build.sh
-      if: ${{ needs.bulk-filter.outputs.runnable == 'true' && (needs.bulk-filter.outputs.src == 'true' || needs.bulk-filter.outputs.ci == 'true') }}
+      if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' && (needs.generated-libraries-filter.outputs.src == 'true' || needs.generated-libraries-filter.outputs.ci == 'true') }}
       shell: bash      
       env:
         JOB_TYPE: test
         JOB_NAME: units-8-runtime-${{matrix.java}}
   # detect which libraries have changed
   changes:
-    needs: bulk-filter
-    if: ${{ needs.bulk-filter.outputs.runnable == 'true' }}
+    needs: generated-libraries-filter
+    if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' }}
     runs-on: ubuntu-latest
     permissions:
       pull-requests: read
@@ -353,6 +349,7 @@ jobs:
       with:
         distribution: temurin
         java-version: 11
+        cache: maven
     - run: .kokoro/build.sh
       env:
         BUILD_SUBDIR: ${{matrix.package}}
@@ -372,11 +369,12 @@ jobs:
       with:
         distribution: temurin
         java-version: 17
+        cache: maven
     - run: .kokoro/dependencies.sh
       env:
         BUILD_SUBDIR: ${{matrix.package}}
   required:
-    needs: [ bulk-filter, changes, split-units, split-clirr, split-dependencies ]
+    needs: [ generated-libraries-filter, changes, split-units, split-clirr, split-dependencies ]
     name: conditional-required-check
     if: ${{ always() }} # Always run even if any "needs" jobs fail
     runs-on: ubuntu-22.04
@@ -387,8 +385,8 @@ jobs:
       - name: Success otherwise
         run: echo "Success!"
   windows:
-    needs: bulk-filter
-    if: ${{ needs.bulk-filter.outputs.runnable == 'true' }}
+    needs: generated-libraries-filter
+    if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' }}
     runs-on: windows-latest
     steps:
     - name: Support longpaths
@@ -407,8 +405,8 @@ jobs:
         JOB_TYPE: test
         JOB_NAME: windows-units
   lint:
-    needs: bulk-filter
-    if: ${{ needs.bulk-filter.outputs.runnable == 'true' }}
+    needs: generated-libraries-filter
+    if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' }}
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
@@ -426,8 +424,8 @@ jobs:
         HEAD_SHA: ${{ github.event.pull_request.head.sha || github.sha }}
         BASE_SHA: ${{ github.event.pull_request.base.sha || github.event.before }}
   enforcer:
-    needs: bulk-filter
-    if: ${{ needs.bulk-filter.outputs.runnable == 'true' }}
+    needs: generated-libraries-filter
+    if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' }}
     runs-on: ubuntu-latest
     steps:
     - name: Get current week within the year
@@ -449,8 +447,8 @@ jobs:
     - run: java -version
     - run: mvn -B -ntp enforcer:enforce@enforce -T 1C
   gapic-libraries-bom:
-    needs: bulk-filter
-    if: ${{ needs.bulk-filter.outputs.runnable == 'true' }}
+    needs: generated-libraries-filter
+    if: ${{ needs.generated-libraries-filter.outputs.runnable == 'true' }}
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
diff --git a/.kokoro/build.sh b/.kokoro/build.sh
index 92e714cb451e..85ffe13759f4 100755
--- a/.kokoro/build.sh
+++ b/.kokoro/build.sh
@@ -37,27 +37,28 @@ RETURN_CODE=0
 
 case ${JOB_TYPE} in
   test)
+    MAVEN_GOAL="test"
     if [[ -n "${BUILD_SUBDIR}" ]]
     then
       echo "Compiling and building all modules for ${BUILD_SUBDIR}"
       install_modules "${BUILD_SUBDIR}"
       echo "Running in subdir: ${BUILD_SUBDIR}"
       pushd "${BUILD_SUBDIR}"
-      EXTRA_PROFILE_OPTS=()
     else
-      EXTRA_PROFILE_OPTS=("-PbulkTests")
-      install_modules "sdk-platform-java"
+      # These are pure GAPIC-generated modules with no unit tests to run here; Showcase
+      # integration tests already cover the generated code's behavior, so this pass only
+      # needs to confirm everything compiles.
+      MAVEN_GOAL="compile"
     fi
-    echo "SUREFIRE_JVM_OPT: ${SUREFIRE_JVM_OPT}"
+    echo "MAVEN_GOAL: ${MAVEN_GOAL}"
     retry_with_backoff 3 10 \
-      mvn install \
+      mvn ${MAVEN_GOAL} \
         -B -ntp \
         -Pquick-build \
         -Dorg.slf4j.simpleLogger.showDateTime=true \
         -Dorg.slf4j.simpleLogger.dateTimeFormat=HH:mm:ss:SSS \
         -Dmaven.wagon.http.retryHandler.count=5 \
-        --also-make \
-        ${SUREFIRE_JVM_OPT} "${EXTRA_PROFILE_OPTS[@]}"
+        -T 1C
     RETURN_CODE=$?
 
     if [[ -n "${BUILD_SUBDIR}" ]]
@@ -67,6 +68,31 @@ case ${JOB_TYPE} in
     fi
     echo "Finished running unit tests"
     ;;
+  compile)
+    if [[ -n "${BUILD_SUBDIR}" ]]
+    then
+      echo "Compiling all modules for ${BUILD_SUBDIR}"
+      mvn compile \
+        -B -ntp \
+        -Pquick-build \
+        -Dorg.slf4j.simpleLogger.showDateTime=true \
+        -Dorg.slf4j.simpleLogger.dateTimeFormat=HH:mm:ss:SSS \
+        -Dmaven.wagon.http.retryHandler.count=5 \
+        --projects "${BUILD_SUBDIR}" \
+        --also-make \
+        -T 1C
+    else
+      echo "Compiling all modules in repository"
+      mvn compile \
+        -B -ntp \
+        -Pquick-build \
+        -Dorg.slf4j.simpleLogger.showDateTime=true \
+        -Dorg.slf4j.simpleLogger.dateTimeFormat=HH:mm:ss:SSS \
+        -Dmaven.wagon.http.retryHandler.count=5 \
+        -T 1C
+    fi
+    RETURN_CODE=$?
+    ;;
   install)
     if [[ -n "${BUILD_SUBDIR}" ]]
     then
diff --git a/.kokoro/common.sh b/.kokoro/common.sh
index 9a56b378131a..26de64791fc2 100644
--- a/.kokoro/common.sh
+++ b/.kokoro/common.sh
@@ -416,6 +416,7 @@ function install_modules() {
     printf "Installing submodules:\n%s\n" "$all_submodules"
 
     always_install_deps_list=(
+      'grpc-gcp-java'
       'java-monitoring/google-cloud-monitoring'
       'java-monitoring/google-cloud-monitoring-bom'
       'java-kms/google-cloud-kms'
diff --git a/.kokoro/dependencies.sh b/.kokoro/dependencies.sh
index f341016b5033..4b0c0edcf1f8 100755
--- a/.kokoro/dependencies.sh
+++ b/.kokoro/dependencies.sh
@@ -56,11 +56,11 @@ then
   pushd "${BUILD_SUBDIR}"
 fi
 
-# this should run maven enforcer
-mvn install -B -V -ntp \
-  -Pquick-build -DskipTests=true -Dmaven.javadoc.skip=true -Denforcer.skip=false
+# this should run maven enforcer and compile test dependencies
+mvn test-compile -B -V -ntp \
+  -Pquick-build -DskipTests=true -Dmaven.javadoc.skip=true -Denforcer.skip=false -T 1C
 
-mvn -B dependency:analyze -Pquick-build -DfailOnWarning=true -Dmdep.analyze.skip=false
+mvn -B dependency:analyze -Pquick-build -DfailOnWarning=true -Dmdep.analyze.skip=false -T 1C
 
 if [[ -n "${BUILD_SUBDIR}" ]]
 then
diff --git a/google-cloud-jar-parent/pom.xml b/google-cloud-jar-parent/pom.xml
index b1e26861cab0..d07276a83d6b 100644
--- a/google-cloud-jar-parent/pom.xml
+++ b/google-cloud-jar-parent/pom.xml
@@ -19,7 +19,16 @@
     <relativePath>../google-cloud-pom-parent/pom.xml</relativePath>
   </parent>
   <properties>
-    <skipUnitTests>false</skipUnitTests>
+    <!--
+      Defaults to true: most modules under this parent are pure GAPIC-generated clients whose
+      generated tests aren't worth the CI time. Libraries with handwritten tests worth
+      running (java-spanner, java-bigtable, java-storage, ...) override this back to false in
+      their own top-level pom.xml.
+
+      Wired only into surefire's <skip> (below), not Maven's built-in skipTests, so it skips
+      unit tests without also skipping failsafe/ITs.
+    -->
+    <skipUnitTests>true</skipUnitTests>
     <ignoreNonCompile>true</ignoreNonCompile><!-- maven-dependency-plugin:analyze to skip test scope dependencies -->
   </properties>
 
@@ -197,6 +206,13 @@
         </plugins>
       </build>
     </profile>
+    <profile>
+      <!-- This profile is used to enable GraalVM native image testing -->
+      <id>native</id>
+      <properties>
+        <skipUnitTests>false</skipUnitTests>
+      </properties>
+    </profile>
   </profiles>
 
   <build>
diff --git a/java-bigquery-jdbc/pom.xml b/java-bigquery-jdbc/pom.xml
index 24bd9b89eec9..6bf17a80d920 100644
--- a/java-bigquery-jdbc/pom.xml
+++ b/java-bigquery-jdbc/pom.xml
@@ -27,6 +27,7 @@
   <description>JDBC for BigQuery</description>
 
   <properties>
+    <skipUnitTests>false</skipUnitTests>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <github.global.server>github</github.global.server>
diff --git a/java-bigquery/pom.xml b/java-bigquery/pom.xml
index ee1fcd22dfc8..dbdd5b097703 100644
--- a/java-bigquery/pom.xml
+++ b/java-bigquery/pom.xml
@@ -51,6 +51,7 @@
   </licenses>
 
   <properties>
+    <skipUnitTests>false</skipUnitTests>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <github.global.server>github</github.global.server>
diff --git a/java-bigquerystorage/pom.xml b/java-bigquerystorage/pom.xml
index 5eee00a606fb..72730f284ccb 100644
--- a/java-bigquerystorage/pom.xml
+++ b/java-bigquerystorage/pom.xml
@@ -51,6 +51,7 @@
   </licenses>
 
   <properties>
+    <skipUnitTests>false</skipUnitTests>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <project.protobuf-java.version>3.25.4</project.protobuf-java.version>
diff --git a/java-bigtable/pom.xml b/java-bigtable/pom.xml
index c6bd75e5f4f7..828dc7af906d 100644
--- a/java-bigtable/pom.xml
+++ b/java-bigtable/pom.xml
@@ -139,6 +139,7 @@
     </licenses>
 
     <properties>
+    <skipUnitTests>false</skipUnitTests>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
         <github.global.server>github</github.global.server>
diff --git a/java-common-protos/pom.xml b/java-common-protos/pom.xml
index c394d6e0e109..4742ee359174 100644
--- a/java-common-protos/pom.xml
+++ b/java-common-protos/pom.xml
@@ -39,6 +39,7 @@
   </licenses>
 
   <properties>
+    <skipUnitTests>false</skipUnitTests>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <github.global.server>github</github.global.server>
diff --git a/java-datastore/pom.xml b/java-datastore/pom.xml
index 674bdac579f4..81d36bac48b6 100644
--- a/java-datastore/pom.xml
+++ b/java-datastore/pom.xml
@@ -139,6 +139,7 @@
   </licenses>
 
   <properties>
+    <skipUnitTests>false</skipUnitTests>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <github.global.server>github</github.global.server>
diff --git a/java-dns/pom.xml b/java-dns/pom.xml
index 128eacde4b6a..d147937ceb51 100644
--- a/java-dns/pom.xml
+++ b/java-dns/pom.xml
@@ -18,6 +18,7 @@
   </parent>
 
   <properties>
+    <skipUnitTests>false</skipUnitTests>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <github.global.server>github</github.global.server>
diff --git a/java-firestore/google-cloud-firestore-admin/pom.xml b/java-firestore/google-cloud-firestore-admin/pom.xml
index 74f2bcbb25f2..c8b77288446a 100644
--- a/java-firestore/google-cloud-firestore-admin/pom.xml
+++ b/java-firestore/google-cloud-firestore-admin/pom.xml
@@ -15,6 +15,9 @@
     <artifactId>google-cloud-firestore-parent</artifactId>
     <version>3.46.0-SNAPSHOT</version><!-- {x-version-update:google-cloud-firestore:current} -->
   </parent>
+  <properties>
+    <skipUnitTests>true</skipUnitTests>
+  </properties>
   <dependencies>
     <dependency>
       <groupId>com.google.api.grpc</groupId>
diff --git a/java-firestore/pom.xml b/java-firestore/pom.xml
index 04b20ffa9e6a..b2e833b98129 100644
--- a/java-firestore/pom.xml
+++ b/java-firestore/pom.xml
@@ -139,6 +139,7 @@
   </licenses>
 
   <properties>
+    <skipUnitTests>false</skipUnitTests>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <github.global.server>github</github.global.server>
diff --git a/java-iam/pom.xml b/java-iam/pom.xml
index 38e68f14a1f7..1f9b5b192c94 100644
--- a/java-iam/pom.xml
+++ b/java-iam/pom.xml
@@ -39,6 +39,7 @@
   </licenses>
 
   <properties>
+    <skipUnitTests>false</skipUnitTests>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <github.global.server>github</github.global.server>
diff --git a/java-logging-logback/pom.xml b/java-logging-logback/pom.xml
index daf8f4b9d831..05b4b20bb2f0 100644
--- a/java-logging-logback/pom.xml
+++ b/java-logging-logback/pom.xml
@@ -14,6 +14,7 @@
   </description>
 
   <properties>
+    <skipUnitTests>false</skipUnitTests>
     <logback.version>1.2.13</logback.version>
     <easymock.version>5.6.0</easymock.version>
     <truth.version>1.4.4</truth.version>
diff --git a/java-logging/pom.xml b/java-logging/pom.xml
index a1d584eb2611..a39c48bb8334 100644
--- a/java-logging/pom.xml
+++ b/java-logging/pom.xml
@@ -51,6 +51,7 @@
   </licenses>
 
   <properties>
+    <skipUnitTests>false</skipUnitTests>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <github.global.server>github</github.global.server>
diff --git a/java-notification/pom.xml b/java-notification/pom.xml
index ac93556a90a7..9857d5bef462 100644
--- a/java-notification/pom.xml
+++ b/java-notification/pom.xml
@@ -19,6 +19,7 @@
     <relativePath>../google-cloud-jar-parent/pom.xml</relativePath>
   </parent>
   <properties>
+    <skipUnitTests>false</skipUnitTests>
     <site.installationModule>google-cloud-notification</site.installationModule>
   </properties>
   <dependencyManagement>
diff --git a/java-pubsub/pom.xml b/java-pubsub/pom.xml
index 21d3534d373d..fdf5bb8a449f 100644
--- a/java-pubsub/pom.xml
+++ b/java-pubsub/pom.xml
@@ -51,6 +51,7 @@
   </licenses>
 
   <properties>
+    <skipUnitTests>false</skipUnitTests>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <github.global.server>github</github.global.server>
diff --git a/java-shared-config/native-image-shared-config/pom.xml b/java-shared-config/native-image-shared-config/pom.xml
index 554e6bca9bd0..747178a74d3e 100644
--- a/java-shared-config/native-image-shared-config/pom.xml
+++ b/java-shared-config/native-image-shared-config/pom.xml
@@ -227,6 +227,9 @@
     <profile>
       <!-- This profile is used to enable GraalVM native image testing -->
       <id>native</id>
+      <properties>
+        <skipUnitTests>false</skipUnitTests>
+      </properties>
       <dependencies>
         <!-- Add this dependency to resolve class org.opentest4j.TestAbortedException -->
         <dependency>
diff --git a/java-showcase/pom.xml b/java-showcase/pom.xml
index d5e4704dd22f..04eb5813f350 100644
--- a/java-showcase/pom.xml
+++ b/java-showcase/pom.xml
@@ -17,6 +17,7 @@
   </parent>
 
   <properties>
+    <skipUnitTests>false</skipUnitTests>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <github.global.server>github</github.global.server>
diff --git a/java-spanner-jdbc/pom.xml b/java-spanner-jdbc/pom.xml
index e5ef2d1a4a46..844d846172d8 100644
--- a/java-spanner-jdbc/pom.xml
+++ b/java-spanner-jdbc/pom.xml
@@ -49,6 +49,7 @@
     </license>
   </licenses>
   <properties>
+    <skipUnitTests>false</skipUnitTests>
     <site.installationModule>google-cloud-spanner-jdbc</site.installationModule>
     <junit.version>4.13.2</junit.version>
     <findbugs.version>3.0.2</findbugs.version>
diff --git a/java-spanner/pom.xml b/java-spanner/pom.xml
index d2bf601f3905..196edb6a446b 100644
--- a/java-spanner/pom.xml
+++ b/java-spanner/pom.xml
@@ -51,6 +51,7 @@
   </licenses>
 
   <properties>
+    <skipUnitTests>false</skipUnitTests>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <github.global.server>github</github.global.server>
diff --git a/java-storage-nio/pom.xml b/java-storage-nio/pom.xml
index 398d154a9ba4..cedd12514b91 100644
--- a/java-storage-nio/pom.xml
+++ b/java-storage-nio/pom.xml
@@ -60,6 +60,7 @@
   </licenses>
 
   <properties>
+    <skipUnitTests>false</skipUnitTests>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <github.global.server>github</github.global.server>
diff --git a/java-storage/gapic-google-cloud-storage-v2/pom.xml b/java-storage/gapic-google-cloud-storage-v2/pom.xml
index 8a58812a9987..1b7885ef69b4 100644
--- a/java-storage/gapic-google-cloud-storage-v2/pom.xml
+++ b/java-storage/gapic-google-cloud-storage-v2/pom.xml
@@ -12,6 +12,9 @@
     <artifactId>google-cloud-storage-parent</artifactId>
     <version>2.72.0-SNAPSHOT</version><!-- {x-version-update:google-cloud-storage:current} -->
   </parent>
+  <properties>
+    <skipUnitTests>true</skipUnitTests>
+  </properties>
   <dependencies>
     <dependency>
       <groupId>io.grpc</groupId>
diff --git a/java-storage/pom.xml b/java-storage/pom.xml
index 2a22db9081f3..1eb019c1310f 100644
--- a/java-storage/pom.xml
+++ b/java-storage/pom.xml
@@ -51,6 +51,7 @@
   </licenses>
 
   <properties>
+    <skipUnitTests>false</skipUnitTests>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <github.global.server>github</github.global.server>
diff --git a/sdk-platform-java/gapic-generator-java-pom-parent/pom.xml b/sdk-platform-java/gapic-generator-java-pom-parent/pom.xml
index 304f7e258e4f..03f4d51db33b 100644
--- a/sdk-platform-java/gapic-generator-java-pom-parent/pom.xml
+++ b/sdk-platform-java/gapic-generator-java-pom-parent/pom.xml
@@ -20,6 +20,16 @@
   </parent>
 
   <properties>
+    <!--
+      Defaults to false: unlike google-cloud-jar-parent's GAPIC-generated clients, the
+      modules here (gax-java, gapic-generator-java, java-core, ...) have handwritten tests
+      worth running by default.
+
+      Wired only into surefire's <skip> below, not maven.test.skip, so -DskipUnitTests=true
+      skips unit test execution but never compilation: google-cloud-core's test-jar is a
+      test-scope dependency of several client libraries in the same root reactor, and
+      skipping its compilation would break their dependency resolution.
+    -->
     <skipUnitTests>false</skipUnitTests>
     <checkstyle.header.file>java.header</checkstyle.header.file>
     <maven.compiler.release>8</maven.compiler.release>
@@ -224,7 +234,11 @@
         </plugins>
       </build>
     </profile>
-    <!-- skip tests if bulkTests profile is enabled (when testing the rest of the monorepo) -->
+    <!--
+      skip tests if bulkTests profile is enabled (when testing the rest of the monorepo).
+      Uses skipTests rather than skipUnitTests since both surefire and failsafe honor it,
+      skipping ITs along with unit tests.
+    -->
     <profile>
       <id>bulkTests</id>
       <properties>