diff --git a/.github/workflows/testing.yml b/.github/workflows/testing.yml
index 999bb65e..35873b19 100644
--- a/.github/workflows/testing.yml
+++ b/.github/workflows/testing.yml
@@ -16,7 +16,7 @@ jobs:
       - uses: actions/checkout@v2
       - uses: actions/setup-java@v2
         with:
-          java-version: '8'
+          java-version: '11'
           distribution: 'temurin'
       - uses: gradle/gradle-build-action@v2
         with:
@@ -32,7 +32,7 @@ jobs:
       - uses: actions/checkout@v2
       - uses: actions/setup-java@v2
         with:
-          java-version: '8'
+          java-version: '11'
           distribution: 'temurin'
       - uses: gradle/gradle-build-action@v2
         with:
@@ -45,7 +45,7 @@ jobs:
       - uses: actions/checkout@v2
       - uses: actions/setup-java@v2
         with:
-          java-version: '8'
+          java-version: '11'
           distribution: 'temurin'
       - uses: gradle/gradle-build-action@v2
         with:
diff --git a/build.gradle b/build.gradle
index 6c16702e..0227c91c 100644
--- a/build.gradle
+++ b/build.gradle
@@ -92,8 +92,8 @@ codenarc {
     toolVersion = "1.4"
 }
 
-sourceCompatibility = JavaVersion.VERSION_1_7
-targetCompatibility = JavaVersion.VERSION_1_7
+sourceCompatibility = JavaVersion.VERSION_1_8
+targetCompatibility = JavaVersion.VERSION_1_8
 
 tasks.withType(GenerateModuleMetadata) {
   enabled = false
@@ -170,16 +170,6 @@ pluginBundle {
   }
 }
 
-// Releases must be built on Java 1.8.
-tasks.create("checkJavaVersion").doLast {
-  JavaVersion javaVersion = JavaVersion.current()
-  if (!javaVersion.isJava8()) {
-    throw new GradleException(
-        "The plugin must be published under Java 1.8 but ${javaVersion} is found")
-  }
-}
-[uploadArchives, publishPlugins]*.dependsOn checkJavaVersion
-
 if (System.env.CI == 'true') {
   // Normally html output is more user friendly,
   // but we want a console printable file for CI logs
diff --git a/src/test/groovy/com/google/protobuf/gradle/AndroidProjectDetectionTest.groovy b/src/test/groovy/com/google/protobuf/gradle/AndroidProjectDetectionTest.groovy
index a4a7008b..e66a60d8 100644
--- a/src/test/groovy/com/google/protobuf/gradle/AndroidProjectDetectionTest.groovy
+++ b/src/test/groovy/com/google/protobuf/gradle/AndroidProjectDetectionTest.groovy
@@ -13,8 +13,8 @@ import spock.lang.Unroll
  */
 @CompileDynamic
 class AndroidProjectDetectionTest extends Specification {
-  private static final List<String> GRADLE_VERSION = ["5.6"]
-  private static final List<String> ANDROID_PLUGIN_VERSION = ["3.5.0"]
+  private static final List<String> GRADLE_VERSION = ["5.6", "7.4.2"]
+  private static final List<String> ANDROID_PLUGIN_VERSION = ["3.5.0", "7.2.1"]
 
   static void appendUtilIsAndroidProjectCheckTask(File buildFile, boolean assertResult) {
     buildFile << """
diff --git a/src/test/groovy/com/google/protobuf/gradle/ProtobufAndroidPluginKotlinTest.groovy b/src/test/groovy/com/google/protobuf/gradle/ProtobufAndroidPluginKotlinTest.groovy
index 555c0ffb..a5540cad 100644
--- a/src/test/groovy/com/google/protobuf/gradle/ProtobufAndroidPluginKotlinTest.groovy
+++ b/src/test/groovy/com/google/protobuf/gradle/ProtobufAndroidPluginKotlinTest.groovy
@@ -10,9 +10,9 @@ import spock.lang.Unroll
 
 @CompileDynamic
 class ProtobufAndroidPluginKotlinTest extends Specification {
-  private static final List<String> GRADLE_VERSION = ["5.6", "6.5-milestone-1"]
-  private static final List<String> ANDROID_PLUGIN_VERSION = ["3.5.0", "4.1.0-alpha10"]
-  private static final List<String> KOTLIN_VERSION = ["1.3.20"]
+  private static final List<String> GRADLE_VERSION = ["5.6", "6.5-milestone-1", "7.4.2"]
+  private static final List<String> ANDROID_PLUGIN_VERSION = ["3.5.0", "4.1.0-alpha10", "7.2.1"]
+  private static final List<String> KOTLIN_VERSION = ["1.3.20", "1.3.20", "1.3.40"]
 
   /**
    * This test may take a significant amount of Gradle daemon Metaspace memory in some
@@ -48,6 +48,6 @@ class ProtobufAndroidPluginKotlinTest extends Specification {
     where:
     agpVersion << ANDROID_PLUGIN_VERSION
     gradleVersion << GRADLE_VERSION
-    kotlinVersion << KOTLIN_VERSION + KOTLIN_VERSION
+    kotlinVersion << KOTLIN_VERSION
     }
 }
diff --git a/src/test/groovy/com/google/protobuf/gradle/ProtobufAndroidPluginTest.groovy b/src/test/groovy/com/google/protobuf/gradle/ProtobufAndroidPluginTest.groovy
index 300f8b3a..bebbf83c 100644
--- a/src/test/groovy/com/google/protobuf/gradle/ProtobufAndroidPluginTest.groovy
+++ b/src/test/groovy/com/google/protobuf/gradle/ProtobufAndroidPluginTest.groovy
@@ -15,8 +15,8 @@ import spock.lang.Unroll
  */
 @CompileDynamic
 class ProtobufAndroidPluginTest extends Specification {
-  private static final List<String> GRADLE_VERSION = ["5.6", "6.5", "6.8"]
-  private static final List<String> ANDROID_PLUGIN_VERSION = ["3.5.0", "4.1.0", "4.2.0-alpha10"]
+  private static final List<String> GRADLE_VERSION = ["5.6", "6.5", "6.8", "7.4.2"]
+  private static final List<String> ANDROID_PLUGIN_VERSION = ["3.5.0", "4.1.0", "4.2.0-alpha10", "7.2.1"]
 
   @Unroll
   void "testProjectAndroid should be successfully executed [android #agpVersion, gradle #gradleVersion]"() {
diff --git a/src/test/groovy/com/google/protobuf/gradle/ProtobufJavaPluginTest.groovy b/src/test/groovy/com/google/protobuf/gradle/ProtobufJavaPluginTest.groovy
index 214ce016..9a14d4a9 100644
--- a/src/test/groovy/com/google/protobuf/gradle/ProtobufJavaPluginTest.groovy
+++ b/src/test/groovy/com/google/protobuf/gradle/ProtobufJavaPluginTest.groovy
@@ -16,8 +16,8 @@ import spock.lang.Unroll
 @CompileDynamic
 class ProtobufJavaPluginTest extends Specification {
   // Current supported version is Gradle 5+.
-  private static final List<String> GRADLE_VERSIONS = ["5.6", "6.0", "6.7.1"]
-  private static final List<String> KOTLIN_VERSIONS = ["1.3.20", "1.3.30"]
+  private static final List<String> GRADLE_VERSIONS = ["5.6", "6.0", "6.7.1", "7.4.2"]
+  private static final List<String> KOTLIN_VERSIONS = ["1.3.20", "1.3.30", "1.3.40"]
 
   void "testApplying java and com.google.protobuf adds corresponding task to project"() {
     given: "a basic project with java and com.google.protobuf"
diff --git a/src/test/groovy/com/google/protobuf/gradle/ProtobufKotlinDslCopySpecTest.groovy b/src/test/groovy/com/google/protobuf/gradle/ProtobufKotlinDslCopySpecTest.groovy
index 84404fc9..526816d5 100644
--- a/src/test/groovy/com/google/protobuf/gradle/ProtobufKotlinDslCopySpecTest.groovy
+++ b/src/test/groovy/com/google/protobuf/gradle/ProtobufKotlinDslCopySpecTest.groovy
@@ -12,7 +12,7 @@ import spock.lang.Unroll
  */
 @CompileDynamic
 class ProtobufKotlinDslCopySpecTest extends Specification {
-  private static final List<String> GRADLE_VERSIONS = ["5.6", "6.0", "6.7.1", "7.0"]
+  private static final List<String> GRADLE_VERSIONS = ["5.6", "6.0", "6.7.1", "7.0", "7.4.2"]
 
   @Unroll
   void "testProjectKotlinDslCopySpec should declare explicit copy spec [gradle #gradleVersion]"() {
diff --git a/src/test/groovy/com/google/protobuf/gradle/ProtobufKotlinDslPluginTest.groovy b/src/test/groovy/com/google/protobuf/gradle/ProtobufKotlinDslPluginTest.groovy
index e9125d39..495aa573 100644
--- a/src/test/groovy/com/google/protobuf/gradle/ProtobufKotlinDslPluginTest.groovy
+++ b/src/test/groovy/com/google/protobuf/gradle/ProtobufKotlinDslPluginTest.groovy
@@ -14,8 +14,8 @@ import spock.lang.Unroll
  */
 @CompileDynamic
 class ProtobufKotlinDslPluginTest extends Specification {
-  private static final List<String> GRADLE_VERSIONS = ["5.6", "6.1.1", "6.5"]
-  private static final List<String> ANDROID_PLUGIN_VERSION = ["3.5.0", "4.0.0", "4.1.0"]
+  private static final List<String> GRADLE_VERSIONS = ["5.6", "6.1.1", "6.5", "7.4.2"]
+  private static final List<String> ANDROID_PLUGIN_VERSION = ["3.5.0", "4.0.0", "4.1.0", "7.2.1"]
 
   @Unroll
   void "testProjectKotlinDsl should be successfully executed (java-only project) [gradle #gradleVersion]"() {
diff --git a/src/test/groovy/com/google/protobuf/gradle/ProtobufPluginTestHelper.groovy b/src/test/groovy/com/google/protobuf/gradle/ProtobufPluginTestHelper.groovy
index a00a5a12..18e1b711 100644
--- a/src/test/groovy/com/google/protobuf/gradle/ProtobufPluginTestHelper.groovy
+++ b/src/test/groovy/com/google/protobuf/gradle/ProtobufPluginTestHelper.groovy
@@ -2,6 +2,7 @@ package com.google.protobuf.gradle
 
 import groovy.transform.CompileDynamic
 import org.apache.commons.io.FileUtils
+import org.gradle.api.GradleException
 import org.gradle.testkit.runner.BuildResult
 import org.gradle.testkit.runner.GradleRunner
 
@@ -40,7 +41,14 @@ final class ProtobufPluginTestHelper {
     }
     List<String> args = arguments.toList()
     // set android build cache to avoid using home directory on CI.
-    args.add("-Pandroid.buildCacheDir=$localBuildCache".toString())
+    // More details about that if can be found here:
+    // https://developer.android.com/studio/releases/gradle-plugin.html#build-cache-removed
+    if (gradleVersion.take(1) == "7") { // TODO: improve version comparison
+      args.add("-PbuildCache.local.directory=$localBuildCache".toString())
+      args.add("-PbuildCache.local.removeUnusedEntriesAfterDays=7".toString())
+    } else {
+      args.add("-Pandroid.buildCacheDir=$localBuildCache".toString())
+    }
     args.add(fullPathTask)
     args.add("--stacktrace")
     return GradleRunner.create()
@@ -144,6 +152,7 @@ buildscript {
     }
 }
 """
+
         previousFileContents.each { line ->
           buildFile << line + '\n'
         }
diff --git a/testProjectAndroidBare/build_base.gradle b/testProjectAndroidBare/build_base.gradle
index d7a6479f..37d40038 100644
--- a/testProjectAndroidBare/build_base.gradle
+++ b/testProjectAndroidBare/build_base.gradle
@@ -11,7 +11,7 @@ android {
   }
 
   compileOptions {
-    sourceCompatibility = JavaVersion.VERSION_1_7
-    targetCompatibility = JavaVersion.VERSION_1_7
+    sourceCompatibility = JavaVersion.VERSION_1_8
+    targetCompatibility = JavaVersion.VERSION_1_8
   }
 }
diff --git a/testProjectAndroidBase/build_base.gradle b/testProjectAndroidBase/build_base.gradle
index cc223968..29f9fc16 100644
--- a/testProjectAndroidBase/build_base.gradle
+++ b/testProjectAndroidBase/build_base.gradle
@@ -47,8 +47,8 @@ android {
     }
 
     compileOptions {
-        sourceCompatibility = JavaVersion.VERSION_1_7
-        targetCompatibility = JavaVersion.VERSION_1_7
+        sourceCompatibility = JavaVersion.VERSION_1_8
+        targetCompatibility = JavaVersion.VERSION_1_8
     }
 
     packagingOptions {
diff --git a/testProjectAndroidDependentBase/build_base.gradle b/testProjectAndroidDependentBase/build_base.gradle
index b742266a..165aea5c 100644
--- a/testProjectAndroidDependentBase/build_base.gradle
+++ b/testProjectAndroidDependentBase/build_base.gradle
@@ -47,8 +47,8 @@ android {
     }
 
     compileOptions {
-        sourceCompatibility = JavaVersion.VERSION_1_7
-        targetCompatibility = JavaVersion.VERSION_1_7
+        sourceCompatibility = JavaVersion.VERSION_1_8
+        targetCompatibility = JavaVersion.VERSION_1_8
     }
 
     packagingOptions {
diff --git a/testProjectAndroidKotlinDsl/build.gradle.kts b/testProjectAndroidKotlinDsl/build.gradle.kts
index 514388ab..f8a969b5 100644
--- a/testProjectAndroidKotlinDsl/build.gradle.kts
+++ b/testProjectAndroidKotlinDsl/build.gradle.kts
@@ -77,8 +77,8 @@ android {
   }
 
   compileOptions {
-    sourceCompatibility = JavaVersion.VERSION_1_7
-    targetCompatibility = JavaVersion.VERSION_1_7
+    sourceCompatibility = JavaVersion.VERSION_1_8
+    targetCompatibility = JavaVersion.VERSION_1_8
   }
 
   packagingOptions {
@@ -130,6 +130,7 @@ protobuf {
 }
 
 dependencies {
+  implementation("org.jetbrains.kotlin:kotlin-stdlib:$kotlinVersion")
   implementation("com.android.support:appcompat-v7:23.4.0")
   implementation("com.squareup.okhttp:okhttp:2.7.5")
   implementation("javax.annotation:javax.annotation-api:1.2")
diff --git a/testProjectAndroidLibrary/build.gradle b/testProjectAndroidLibrary/build.gradle
index 21d23dda..4539129c 100644
--- a/testProjectAndroidLibrary/build.gradle
+++ b/testProjectAndroidLibrary/build.gradle
@@ -36,8 +36,8 @@ android {
     }
 
     compileOptions {
-        sourceCompatibility = JavaVersion.VERSION_1_7
-        targetCompatibility = JavaVersion.VERSION_1_7
+        sourceCompatibility = JavaVersion.VERSION_1_8
+        targetCompatibility = JavaVersion.VERSION_1_8
     }
 
     // https://github.com/square/okio/issues/58
diff --git a/testProjectBase/build_base.gradle b/testProjectBase/build_base.gradle
index d29f5127..fb8455e4 100644
--- a/testProjectBase/build_base.gradle
+++ b/testProjectBase/build_base.gradle
@@ -5,8 +5,8 @@ repositories {
     maven { url "https://plugins.gradle.org/m2/" }
 }
 
-sourceCompatibility = JavaVersion.VERSION_1_7
-targetCompatibility = JavaVersion.VERSION_1_7
+sourceCompatibility = JavaVersion.VERSION_1_8
+targetCompatibility = JavaVersion.VERSION_1_8
 
 sourceSets {
   grpc {
@@ -25,12 +25,14 @@ dependencies {
   testProtobuf files("lib/protos-test.tar.gz")
 
   implementation protobufDep
+  implementation 'javax.annotation:javax.annotation-api:1.3.2'
   testImplementation 'junit:junit:4.12'
   // KotlinFooTest.kt requires reflection utilities
   testImplementation "org.jetbrains.kotlin:kotlin-reflect:1.2.0"
   grpcImplementation protobufDep
   grpcImplementation 'io.grpc:grpc-stub:1.0.0-pre2'
   grpcImplementation 'io.grpc:grpc-protobuf:1.0.0-pre2'
+  grpcImplementation 'javax.annotation:javax.annotation-api:1.3.2'
 }
 
 protobuf {
@@ -60,6 +62,8 @@ jar {
     from sourceSet.output
     dependsOn sourceSet.getCompileTaskName('java')
   }
+
+  duplicatesStrategy(DuplicatesStrategy.INCLUDE)
 }
 
 def assertJavaCompileHasProtoGeneratedDir(String sourceSet, Collection<String> codegenPlugins) {
diff --git a/testProjectKotlin/build.gradle b/testProjectKotlin/build.gradle
index e455c461..e12dd451 100644
--- a/testProjectKotlin/build.gradle
+++ b/testProjectKotlin/build.gradle
@@ -5,3 +5,7 @@ plugins {
   id 'com.google.protobuf'
 }
 apply from: 'build_base.gradle'
+
+dependencies {
+  implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlinVersion"
+}
diff --git a/testProjectKotlinDslBase/build.gradle.kts b/testProjectKotlinDslBase/build.gradle.kts
index 88c36452..42fddab9 100644
--- a/testProjectKotlinDslBase/build.gradle.kts
+++ b/testProjectKotlinDslBase/build.gradle.kts
@@ -18,8 +18,8 @@ repositories {
 }
 
 java {
-    sourceCompatibility = JavaVersion.VERSION_1_7
-    targetCompatibility = JavaVersion.VERSION_1_7
+    sourceCompatibility = JavaVersion.VERSION_1_8
+    targetCompatibility = JavaVersion.VERSION_1_8
 }
 
 sourceSets {
@@ -36,6 +36,7 @@ val grpcImplementation = configurations.getByName("grpcImplementation")
 val protobufDep = "com.google.protobuf:protobuf-java:3.0.0"
 
 dependencies {
+    implementation("org.jetbrains.kotlin:kotlin-stdlib:$kotlinVersion")
     protobuf(files("lib/protos.tar.gz"))
     protobuf(files("ext/"))
     testProtobuf(files("lib/protos-test.tar.gz"))
diff --git a/testProjectKotlinDslCopySpec/build.gradle.kts b/testProjectKotlinDslCopySpec/build.gradle.kts
index 887598aa..bbcd8a66 100644
--- a/testProjectKotlinDslCopySpec/build.gradle.kts
+++ b/testProjectKotlinDslCopySpec/build.gradle.kts
@@ -30,6 +30,7 @@ val protobufDepVersion = "3.0.0"
 val grpcVersion = "1.37.0"
 
 dependencies {
+  implementation("org.jetbrains.kotlin:kotlin-stdlib:$kotlinVersion")
   implementation("io.grpc:grpc-protobuf:$grpcVersion")
   implementation("io.grpc:grpc-stub:$grpcVersion")
   implementation("com.google.protobuf:protobuf-java:$protobufDepVersion")
diff --git a/testProjectLite/build.gradle b/testProjectLite/build.gradle
index 11cf2c88..62239c94 100644
--- a/testProjectLite/build.gradle
+++ b/testProjectLite/build.gradle
@@ -9,8 +9,8 @@ repositories {
     maven { url "https://plugins.gradle.org/m2/" }
 }
 
-sourceCompatibility = JavaVersion.VERSION_1_7
-targetCompatibility = JavaVersion.VERSION_1_7
+sourceCompatibility = JavaVersion.VERSION_1_8
+targetCompatibility = JavaVersion.VERSION_1_8
 
 dependencies {
     implementation 'com.google.protobuf:protobuf-lite:3.0.0'