diff --git a/.github/workflows/integTest-sample-gradle-plugin.yml b/.github/workflows/integTest-sample-gradle-plugin.yml
new file mode 100644
index 0000000..148ac12
--- /dev/null
+++ b/.github/workflows/integTest-sample-gradle-plugin.yml
@@ -0,0 +1,41 @@
+name: Test caching with Gradle Plugin project using TestKit
+
+on:
+  pull_request:
+    types: [assigned, review_requested]
+  push:
+  workflow_dispatch:
+
+env:
+  GRADLE_BUILD_ACTION_CACHE_KEY_PREFIX: ${{github.workflow}}#${{github.run_number}}-
+  GRADLE_BUILD_ACTION_CACHE_DEBUG_ENABLED: true
+
+jobs:
+  seed-build:
+    strategy:
+      matrix:
+        os: [ubuntu-latest, windows-latest]
+    runs-on: ${{ matrix.os }}
+    steps:
+    - name: Checkout sources
+      uses: actions/checkout@v2
+    - name: Setup Gradle
+      uses: ./
+    - name: Build gradle-plugin project
+      working-directory: __tests__/samples/gradle-plugin
+      run: ./gradlew build
+
+  verify-build:
+    needs: seed-build
+    strategy:
+      matrix:
+        os: [ubuntu-latest, windows-latest]
+    runs-on: ${{ matrix.os }}
+    steps:
+    - name: Checkout sources
+      uses: actions/checkout@v2
+    - name: Setup Gradle
+      uses: ./
+    - name: Build gradle-plugin project
+      working-directory: __tests__/samples/gradle-plugin
+      run: ./gradlew build --offline
diff --git a/.github/workflows/integTest-kotlin-dsl.yml b/.github/workflows/integTest-sample-kotlin-dsl.yml
similarity index 83%
rename from .github/workflows/integTest-kotlin-dsl.yml
rename to .github/workflows/integTest-sample-kotlin-dsl.yml
index cb909ae..c9b7655 100644
--- a/.github/workflows/integTest-kotlin-dsl.yml
+++ b/.github/workflows/integTest-sample-kotlin-dsl.yml
@@ -11,7 +11,6 @@ env:
   GRADLE_BUILD_ACTION_CACHE_DEBUG_ENABLED: true
 
 jobs:
-  # Use kotlin-dsl project to verify caching of generated jars and compiled scripts
   seed-build:
     strategy:
       matrix:
@@ -24,9 +23,8 @@ jobs:
       uses: ./
     - name: Build kotlin-dsl project
       working-directory: __tests__/samples/kotlin-dsl
-      run: ./gradlew test
+      run: ./gradlew build
 
-  # Check that the build can run --offline
   verify-build:
     needs: seed-build
     strategy:
@@ -40,4 +38,4 @@ jobs:
       uses: ./
     - name: Build kotlin-dsl project
       working-directory: __tests__/samples/kotlin-dsl
-      run: ./gradlew test --offline
+      run: ./gradlew build --offline
diff --git a/__tests__/samples/gradle-plugin/gradle/wrapper/gradle-wrapper.jar b/__tests__/samples/gradle-plugin/gradle/wrapper/gradle-wrapper.jar
new file mode 100644
index 0000000..7454180
Binary files /dev/null and b/__tests__/samples/gradle-plugin/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/__tests__/samples/gradle-plugin/gradle/wrapper/gradle-wrapper.properties b/__tests__/samples/gradle-plugin/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 0000000..e750102
--- /dev/null
+++ b/__tests__/samples/gradle-plugin/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.3-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
diff --git a/__tests__/samples/gradle-plugin/gradlew b/__tests__/samples/gradle-plugin/gradlew
new file mode 100755
index 0000000..1b6c787
--- /dev/null
+++ b/__tests__/samples/gradle-plugin/gradlew
@@ -0,0 +1,234 @@
+#!/bin/sh
+
+#
+# Copyright © 2015-2021 the original authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+##############################################################################
+#
+#   Gradle start up script for POSIX generated by Gradle.
+#
+#   Important for running:
+#
+#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+#       noncompliant, but you have some other compliant shell such as ksh or
+#       bash, then to run this script, type that shell name before the whole
+#       command line, like:
+#
+#           ksh Gradle
+#
+#       Busybox and similar reduced shells will NOT work, because this script
+#       requires all of these POSIX shell features:
+#         * functions;
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#         * compound commands having a testable exit status, especially «case»;
+#         * various built-in commands including «command», «set», and «ulimit».
+#
+#   Important for patching:
+#
+#   (2) This script targets any POSIX shell, so it avoids extensions provided
+#       by Bash, Ksh, etc; in particular arrays are avoided.
+#
+#       The "traditional" practice of packing multiple parameters into a
+#       space-separated string is a well documented source of bugs and security
+#       problems, so this is (mostly) avoided, by progressively accumulating
+#       options in "$@", and eventually passing that to Java.
+#
+#       Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+#       see the in-line comments for details.
+#
+#       There are tweaks for specific operating systems such as AIX, CygWin,
+#       Darwin, MinGW, and NonStop.
+#
+#   (3) This script is generated from the Groovy template
+#       https://github.com/gradle/gradle/blob/master/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       within the Gradle project.
+#
+#       You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+    APP_HOME=${app_path%"${app_path##*/}"}  # leaves a trailing /; empty if no leading path
+    [ -h "$app_path" ]
+do
+    ls=$( ls -ld "$app_path" )
+    link=${ls#*' -> '}
+    case $link in             #(
+      /*)   app_path=$link ;; #(
+      *)    app_path=$APP_HOME$link ;;
+    esac
+done
+
+APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
+
+APP_NAME="Gradle"
+APP_BASE_NAME=${0##*/}
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&2
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in                #(
+  CYGWIN* )         cygwin=true  ;; #(
+  Darwin* )         darwin=true  ;; #(
+  MSYS* | MINGW* )  msys=true    ;; #(
+  NONSTOP* )        nonstop=true ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD=$JAVA_HOME/jre/sh/java
+    else
+        JAVACMD=$JAVA_HOME/bin/java
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD=java
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
+    case $MAX_FD in #(
+      max*)
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        ulimit -n "$MAX_FD" ||
+            warn "Could not set maximum file descriptor limit to $MAX_FD"
+    esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+#   * args from the command line
+#   * the main class name
+#   * -classpath
+#   * -D...appname settings
+#   * --module-path (only if needed)
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+    APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
+
+    JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    for arg do
+        if
+            case $arg in                                #(
+              -*)   false ;;                            # don't mess with options #(
+              /?*)  t=${arg#/} t=/${t%%/*}              # looks like a POSIX filepath
+                    [ -e "$t" ] ;;                      #(
+              *)    false ;;
+            esac
+        then
+            arg=$( cygpath --path --ignore --mixed "$arg" )
+        fi
+        # Roll the args list around exactly as many times as the number of
+        # args, so each arg winds up back in the position where it started, but
+        # possibly modified.
+        #
+        # NB: a `for` loop captures its iteration list before it begins, so
+        # changing the positional parameters here affects neither the number of
+        # iterations, nor the values presented in `arg`.
+        shift                   # remove old arg
+        set -- "$@" "$arg"      # push replacement arg
+    done
+fi
+
+# Collect all arguments for the java command;
+#   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
+#     shell script including quotes and variable substitutions, so put them in
+#     double quotes to make sure that they get re-expanded; and
+#   * put everything else in single quotes, so that it's not re-expanded.
+
+set -- \
+        "-Dorg.gradle.appname=$APP_BASE_NAME" \
+        -classpath "$CLASSPATH" \
+        org.gradle.wrapper.GradleWrapperMain \
+        "$@"
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+#   set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+        printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+        xargs -n1 |
+        sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+        tr '\n' ' '
+    )" '"$@"'
+
+exec "$JAVACMD" "$@"
diff --git a/__tests__/samples/gradle-plugin/gradlew.bat b/__tests__/samples/gradle-plugin/gradlew.bat
new file mode 100644
index 0000000..107acd3
--- /dev/null
+++ b/__tests__/samples/gradle-plugin/gradlew.bat
@@ -0,0 +1,89 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/__tests__/samples/gradle-plugin/plugin/build.gradle b/__tests__/samples/gradle-plugin/plugin/build.gradle
new file mode 100644
index 0000000..e954fb0
--- /dev/null
+++ b/__tests__/samples/gradle-plugin/plugin/build.gradle
@@ -0,0 +1,60 @@
+/*
+ * This file was generated by the Gradle 'init' task.
+ *
+ * This generated file contains a sample Gradle plugin project to get you started.
+ * For more details take a look at the Writing Custom Plugins chapter in the Gradle
+ * User Manual available at https://docs.gradle.org/7.3/userguide/custom_plugins.html
+ * This project uses @Incubating APIs which are subject to change.
+ */
+
+plugins {
+    // Apply the Java Gradle plugin development plugin to add support for developing Gradle plugins
+    id 'java-gradle-plugin'
+}
+
+repositories {
+    // Use Maven Central for resolving dependencies.
+    mavenCentral()
+}
+
+testing {
+    suites {
+        // Configure the built-in test suite
+        test {
+            // Use JUnit Jupiter test framework
+            useJUnitJupiter('5.7.2')
+        }
+
+        // Create a new test suite
+        functionalTest(JvmTestSuite) {
+            dependencies {
+                // functionalTest test suite depends on the production code in tests
+                implementation project
+            }
+
+            targets {
+                all {
+                    // This test suite should run after the built-in test suite has run its tests
+                    testTask.configure { shouldRunAfter(test) } 
+                }
+            }
+        }
+    }
+}
+
+gradlePlugin {
+    // Define the plugin
+    plugins {
+        greeting {
+            id = 'org.example.gradle.plugin.greeting'
+            implementationClass = 'org.example.gradle.plugin.GradlePluginPlugin'
+        }
+    }
+}
+
+gradlePlugin.testSourceSets(sourceSets.functionalTest)
+
+tasks.named('check') {
+    // Include functionalTest as part of the check lifecycle
+    dependsOn(testing.suites.functionalTest)
+}
diff --git a/__tests__/samples/gradle-plugin/plugin/src/functionalTest/java/org/example/gradle/plugin/GradlePluginPluginFunctionalTest.java b/__tests__/samples/gradle-plugin/plugin/src/functionalTest/java/org/example/gradle/plugin/GradlePluginPluginFunctionalTest.java
new file mode 100644
index 0000000..7f17460
--- /dev/null
+++ b/__tests__/samples/gradle-plugin/plugin/src/functionalTest/java/org/example/gradle/plugin/GradlePluginPluginFunctionalTest.java
@@ -0,0 +1,57 @@
+/*
+ * This Java source file was generated by the Gradle 'init' task.
+ */
+package org.example.gradle.plugin;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.Writer;
+import java.io.FileWriter;
+import java.nio.file.Files;
+import org.gradle.testkit.runner.GradleRunner;
+import org.gradle.testkit.runner.BuildResult;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+import static org.junit.jupiter.api.Assertions.*;
+
+/**
+ * A simple functional test for the 'org.example.gradle.plugin.greeting' plugin.
+ */
+class GradlePluginPluginFunctionalTest {
+    @TempDir
+    File projectDir;
+
+    private File getBuildFile() {
+        return new File(projectDir, "build.gradle");
+    }
+
+    private File getSettingsFile() {
+        return new File(projectDir, "settings.gradle");
+    }
+
+    @Test void canRunTaskWithGradle691() throws IOException {
+        writeString(getSettingsFile(), "");
+        writeString(getBuildFile(),
+            "plugins {" +
+            "  id('org.example.gradle.plugin.greeting')" +
+            "}");
+
+        // Run the build
+        GradleRunner runner = GradleRunner.create();
+        runner.forwardOutput();
+        runner.withGradleVersion("6.9.1");
+        runner.withPluginClasspath();
+        runner.withArguments("greeting");
+        runner.withProjectDir(projectDir);
+        BuildResult result = runner.build();
+
+        // Verify the result
+        assertTrue(result.getOutput().contains("Hello from plugin 'org.example.gradle.plugin.greeting'"));
+    }
+
+    private void writeString(File file, String string) throws IOException {
+        try (Writer writer = new FileWriter(file)) {
+            writer.write(string);
+        }
+    }
+}
diff --git a/__tests__/samples/gradle-plugin/plugin/src/main/java/org/example/gradle/plugin/GradlePluginPlugin.java b/__tests__/samples/gradle-plugin/plugin/src/main/java/org/example/gradle/plugin/GradlePluginPlugin.java
new file mode 100644
index 0000000..80dfc76
--- /dev/null
+++ b/__tests__/samples/gradle-plugin/plugin/src/main/java/org/example/gradle/plugin/GradlePluginPlugin.java
@@ -0,0 +1,19 @@
+/*
+ * This Java source file was generated by the Gradle 'init' task.
+ */
+package org.example.gradle.plugin;
+
+import org.gradle.api.Project;
+import org.gradle.api.Plugin;
+
+/**
+ * A simple 'hello world' plugin.
+ */
+public class GradlePluginPlugin implements Plugin<Project> {
+    public void apply(Project project) {
+        // Register a task
+        project.getTasks().register("greeting", task -> {
+            task.doLast(s -> System.out.println("Hello from plugin 'org.example.gradle.plugin.greeting'"));
+        });
+    }
+}
diff --git a/__tests__/samples/gradle-plugin/plugin/src/test/java/org/example/gradle/plugin/GradlePluginPluginTest.java b/__tests__/samples/gradle-plugin/plugin/src/test/java/org/example/gradle/plugin/GradlePluginPluginTest.java
new file mode 100644
index 0000000..c2ee169
--- /dev/null
+++ b/__tests__/samples/gradle-plugin/plugin/src/test/java/org/example/gradle/plugin/GradlePluginPluginTest.java
@@ -0,0 +1,23 @@
+/*
+ * This Java source file was generated by the Gradle 'init' task.
+ */
+package org.example.gradle.plugin;
+
+import org.gradle.testfixtures.ProjectBuilder;
+import org.gradle.api.Project;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
+/**
+ * A simple unit test for the 'org.example.gradle.plugin.greeting' plugin.
+ */
+class GradlePluginPluginTest {
+    @Test void pluginRegistersATask() {
+        // Create a test project and apply the plugin
+        Project project = ProjectBuilder.builder().build();
+        project.getPlugins().apply("org.example.gradle.plugin.greeting");
+
+        // Verify the result
+        assertNotNull(project.getTasks().findByName("greeting"));
+    }
+}
diff --git a/__tests__/samples/gradle-plugin/settings.gradle b/__tests__/samples/gradle-plugin/settings.gradle
new file mode 100644
index 0000000..de78579
--- /dev/null
+++ b/__tests__/samples/gradle-plugin/settings.gradle
@@ -0,0 +1,12 @@
+/*
+ * This file was generated by the Gradle 'init' task.
+ *
+ * The settings file is used to specify which projects to include in your build.
+ *
+ * Detailed information about configuring a multi-project build in Gradle can be found
+ * in the user manual at https://docs.gradle.org/7.3/userguide/multi_project_builds.html
+ * This project uses @Incubating APIs which are subject to change.
+ */
+
+rootProject.name = 'gradle-plugin'
+include('plugin')