diff --git a/README.adoc b/README.adoc
index 14288d6bd..12ec96d94 100644
--- a/README.adoc
+++ b/README.adoc
@@ -1,7 +1,7 @@
 = Asciidoctor Gradle Plugin
 Andres Almiray <https://github.com/aalmiray[@aalmiray]>
-:version: 3.3.2
-:version-published: 3.3.2
+:version: 4.0.0
+:version-published: 4.0.0-alpha.1
 :asciidoc-url: http://asciidoc.org
 :asciidoctor-url: http://asciidoctor.org
 :issues: https://github.com/asciidoctor/asciidoctor-maven-plugin/issues
@@ -20,7 +20,7 @@ Andres Almiray <https://github.com/aalmiray[@aalmiray]>
 :plugin-name: Asciidoctor Gradle plugin
 :project-name: asciidoctor-gradle-plugin
 :project-full-path: asciidoctor/asciidoctor-gradle-plugin
-:github-branch: development-3.x
+:github-branch: development-4.x
 :linkattrs:
 ifndef::env-github[:icons: font]
 ifdef::env-github,env-browser[]
diff --git a/asciidoctoreditorconfig/src/main/groovy/org/asciidoctor/gradle/editorconfig/AsciidoctorEditorConfigPlugin.groovy b/asciidoctoreditorconfig/src/main/groovy/org/asciidoctor/gradle/editorconfig/AsciidoctorEditorConfigPlugin.groovy
index b958b74d5..a64686184 100644
--- a/asciidoctoreditorconfig/src/main/groovy/org/asciidoctor/gradle/editorconfig/AsciidoctorEditorConfigPlugin.groovy
+++ b/asciidoctoreditorconfig/src/main/groovy/org/asciidoctor/gradle/editorconfig/AsciidoctorEditorConfigPlugin.groovy
@@ -33,17 +33,9 @@ class AsciidoctorEditorConfigPlugin implements Plugin<Project> {
     @Override
     void apply(Project project) {
         ProjectOperations.maybeCreateExtension(project)
-        AsciidoctorEditorConfigGenerator task = project.tasks.create(
-            DEFAULT_TASK_NAME,
-            AsciidoctorEditorConfigGenerator
+        project.tasks.register(
+                DEFAULT_TASK_NAME,
+                AsciidoctorEditorConfigGenerator
         )
-        configureIdea(task)
-    }
-
-    void configureIdea(AsciidoctorEditorConfigGenerator aecg) {
-        Project project = aecg.project
-        project.pluginManager.withPlugin('idea') {
-            project.tasks.getByName('ideaModule').dependsOn aecg
-        }
     }
 }
diff --git a/base/build.gradle b/base/build.gradle
index fa0fbf2af..c97543c6c 100644
--- a/base/build.gradle
+++ b/base/build.gradle
@@ -27,6 +27,7 @@ configurations {
     gradleTestCompile.transitive = false
 }
 
+// TODO: Use configurePlugin instead
 gradlePlugin {
     plugins {
         basePlugin {
diff --git a/base/src/intTest/groovy/org/asciidoctor/gradle/base/internal/FunctionalSpecification.groovy b/base/src/intTest/groovy/org/asciidoctor/gradle/base/internal/FunctionalSpecification.groovy
index 79b3e13e6..c27477697 100644
--- a/base/src/intTest/groovy/org/asciidoctor/gradle/base/internal/FunctionalSpecification.groovy
+++ b/base/src/intTest/groovy/org/asciidoctor/gradle/base/internal/FunctionalSpecification.groovy
@@ -31,13 +31,13 @@ import static org.asciidoctor.gradle.testfixtures.FunctionalTestSetup.getOffline
 class FunctionalSpecification extends Specification {
 
     public static final String TEST_PROJECTS_DIR = System.getProperty(
-        'TEST_PROJECTS_DIR',
-        './asciidoctor-gradle-base/src/intTest/projects'
+            'TEST_PROJECTS_DIR',
+            './asciidoctor-gradle-base/src/intTest/projects'
     )
 
     public static final String TEST_REPO_DIR = System.getProperty(
-        'OFFLINE_REPO',
-        './testfixtures/offline-repo/build/repo'
+            'OFFLINE_REPO',
+            './testfixtures/offline-repo/build/repo'
     )
 
     @TempDir
@@ -61,11 +61,11 @@ class FunctionalSpecification extends Specification {
     @CompileStatic
     String getOfflineRepositories(DslType dslType = GROOVY_DSL) {
         dslType == GROOVY_DSL ? getOfflineRepositoriesGroovyDsl(new File(TEST_REPO_DIR)) :
-            getOfflineRepositoriesKotlinDsl(new File(TEST_REPO_DIR))
+                getOfflineRepositoriesKotlinDsl(new File(TEST_REPO_DIR))
     }
 
     File getGroovyBuildFile(String extraContent, String plugin = 'org.asciidoctor.base') {
-        File buildFile = new File(testProjectDir,'build.gradle')
+        File buildFile = new File(testProjectDir, 'build.gradle')
         buildFile << """
             plugins {
                 id '${plugin}'
@@ -79,7 +79,7 @@ class FunctionalSpecification extends Specification {
     }
 
     File getKotlinBuildFile(String extraContent, String plugin = 'org.asciidoctor.base') {
-        File buildFile = new File(testProjectDir,'build.gradle.kts')
+        File buildFile = new File(testProjectDir, 'build.gradle.kts')
         buildFile << """
             plugins {
                 id("${plugin}")
diff --git a/base/src/main/groovy/org/asciidoctor/gradle/base/AbstractDownloadableComponent.java b/base/src/main/groovy/org/asciidoctor/gradle/base/AbstractDownloadableComponent.java
index 33a721135..8d06beec3 100644
--- a/base/src/main/groovy/org/asciidoctor/gradle/base/AbstractDownloadableComponent.java
+++ b/base/src/main/groovy/org/asciidoctor/gradle/base/AbstractDownloadableComponent.java
@@ -21,6 +21,7 @@
 import org.gradle.api.Project;
 import org.gradle.api.UnknownDomainObjectException;
 import org.gradle.api.provider.Provider;
+import org.ysb33r.grolifant.api.core.ClosureUtils;
 import org.ysb33r.grolifant.api.core.ProjectOperations;
 import org.ysb33r.grolifant.api.core.git.AbstractCloudGit;
 import org.ysb33r.grolifant.api.core.git.GitLabArchive;
@@ -40,6 +41,13 @@
  * @since 2.0
  */
 public abstract class AbstractDownloadableComponent<ComponentSrc, ResolvedComponent> {
+
+    protected final ProjectOperations projectOperations;
+    private final Map<String, Callable<ResolvedComponent>> components =
+            new LinkedHashMap<>();
+
+    private final Provider<File> downloadRootProvider;
+
     /**
      * Adds a component source that is available on the local filesystem.
      * <p>
@@ -75,7 +83,9 @@ public void github(final String name, Action<AscGitHubArchive> githubConfig) {
      * @param gitlabConfig Closure to configure a {@link AscGitLabArchive}.
      */
     public void gitlab(final String name, @DelegatesTo(GitLabArchive.class) Closure<?> gitlabConfig) {
-        gitlab(name, x -> gitlabConfig.call(x));
+        AscGitLabArchive archive = new AscGitLabArchive(projectOperations);
+        ClosureUtils.configureItem(archive,gitlabConfig);
+        this.components.put(name, convertible(name, archive));
     }
 
     /**
@@ -179,9 +189,4 @@ private void addCloudGitArchive(
     private String getRelativePathInsideArchive(AbstractCloudGit theme) {
         return ((String) (theme.getProperty("relativePath")));
     }
-
-    private final Map<String, Callable<ResolvedComponent>> components =
-            new LinkedHashMap<>();
-    private final ProjectOperations projectOperations;
-    private final Provider<File> downloadRootProvider;
 }
diff --git a/base/src/main/groovy/org/asciidoctor/gradle/base/AsciidoctorTaskOutputOptions.java b/base/src/main/groovy/org/asciidoctor/gradle/base/AsciidoctorTaskOutputOptions.java
index d921b9deb..4de1102b6 100644
--- a/base/src/main/groovy/org/asciidoctor/gradle/base/AsciidoctorTaskOutputOptions.java
+++ b/base/src/main/groovy/org/asciidoctor/gradle/base/AsciidoctorTaskOutputOptions.java
@@ -16,6 +16,7 @@
 package org.asciidoctor.gradle.base;
 
 import org.gradle.api.tasks.Internal;
+import org.gradle.api.tasks.Nested;
 import org.gradle.api.tasks.OutputDirectories;
 
 import java.io.File;
@@ -109,4 +110,12 @@ void copyResourcesByBackend(
      * @return Output directory.
      */
     File getOutputDirForBackend(final String backendName, final String language);
+
+    /**
+     * Access to the underlying {@link OutputOptions}.
+     *
+     * @return {@link OutputOptions} instance.
+     */
+    @Nested
+    OutputOptions getOutputOptions();
 }
diff --git a/base/src/main/groovy/org/asciidoctor/gradle/base/internal/AsciidoctorAttributes.groovy b/base/src/main/groovy/org/asciidoctor/gradle/base/internal/AsciidoctorAttributes.groovy
index 80381bb1e..3472cbe97 100644
--- a/base/src/main/groovy/org/asciidoctor/gradle/base/internal/AsciidoctorAttributes.groovy
+++ b/base/src/main/groovy/org/asciidoctor/gradle/base/internal/AsciidoctorAttributes.groovy
@@ -90,6 +90,7 @@ class AsciidoctorAttributes {
      * @param workingSourceDir Working source directory from which source documents will be made available.
      * @param seedAttributes Initial attributes set on the task.
      * @param langAttributes Any language specific attributes.
+     * @param tdsAttributes Task-specific default attributes.
      * @param attributeProviders Additional attribute providers.
      * @param lang Language being processed. Can be unset if multi-language feature is not used.
      * @return Attributes ready for serialisation.
@@ -101,7 +102,7 @@ class AsciidoctorAttributes {
             final StringTools stringTools,
             Map<String, ?> seedAttributes,
             Map<String, ?> langAttributes,
-            Map<String, ?> taskSpecificDefaultAttributes,
+            Map<String, ?> tsdAttributes,
             List<AsciidoctorAttributeProvider> attributeProviders,
             Optional<String> lang
     ) {
@@ -115,7 +116,7 @@ class AsciidoctorAttributes {
         Map<String, Object> defaultAttrs = prepareDefaultAttributes(
                 stringTools,
                 attrs,
-                taskSpecificDefaultAttributes,
+                tsdAttributes,
                 lang
         )
         attrs.putAll(defaultAttrs)
diff --git a/base/src/main/groovy/org/asciidoctor/gradle/base/internal/DefaultAsciidoctorOutputOptions.groovy b/base/src/main/groovy/org/asciidoctor/gradle/base/internal/DefaultAsciidoctorOutputOptions.groovy
index 1d4d653d2..fa8f4189b 100644
--- a/base/src/main/groovy/org/asciidoctor/gradle/base/internal/DefaultAsciidoctorOutputOptions.groovy
+++ b/base/src/main/groovy/org/asciidoctor/gradle/base/internal/DefaultAsciidoctorOutputOptions.groovy
@@ -229,4 +229,14 @@ class DefaultAsciidoctorOutputOptions implements AsciidoctorTaskOutputOptions {
                 new File(fileOperations.outputDir, "${language}/${backendName}") :
                 new File(fileOperations.outputDir, language)
     }
+
+    /**
+     * Access to the underlying {@link OutputOptions}.
+     *
+     * @return {@link OutputOptions} instance.
+     */
+    @Override
+    OutputOptions getOutputOptions() {
+        this.configuredOutputOptions
+    }
 }
diff --git a/build.gradle b/build.gradle
index 0dae16f88..5df351178 100644
--- a/build.gradle
+++ b/build.gradle
@@ -18,7 +18,7 @@ plugins {
 //    id 'com.gradle.build-scan' version '3.11.1'
     id 'net.nemerosa.versioning' version '2.6.1' apply false
     id 'com.github.ben-manes.versions' version '0.17.0' apply false
-    id 'com.gradle.plugin-publish' version '1.2.1' apply false
+//    id 'com.gradle.plugin-publish' version "" apply false
     id 'com.github.hierynomus.license' version '0.16.1' apply false
     id 'com.github.kt3k.coveralls' version '2.8.2' apply false
     id 'net.ossindex.audit' version '0.1.1' apply false
@@ -136,6 +136,17 @@ subprojects {
                 }
             }
 
+            configurations.all {
+                resolutionStrategy {
+                    eachDependency { DependencyResolveDetails details ->
+                        if (details.requested.group == 'org.codehaus.groovy') {
+                            details.useVersion GroovySystem.version
+                            details.because 'THe same version as Grodale Groovy is required'
+                        }
+                    }
+                }
+            }
+
             audit {
                 failOnError = false
             }
diff --git a/buildSrc/build.gradle b/buildSrc/build.gradle
index 7ff125fd8..4767c2aa1 100644
--- a/buildSrc/build.gradle
+++ b/buildSrc/build.gradle
@@ -17,6 +17,7 @@ repositories {
 dependencies {
     implementation localGroovy()
     implementation gradleApi()
+    implementation "com.gradle.publish:plugin-publish-plugin:${gradleProperties.pluginPublishPlugin}"
     api "org.ysb33r.gradle:nodejs-gradle-plugin:${gradleProperties.nodejsGradleVersion}"
     api "org.ysb33r.gradle:grolifant-herd:${gradleProperties.grolifantVersion}"
 }
diff --git a/buildSrc/src/main/groovy/AsciidoctorGradlePluginProject.groovy b/buildSrc/src/main/groovy/AsciidoctorGradlePluginProject.groovy
index 12e68ae3d..cfbf46abd 100644
--- a/buildSrc/src/main/groovy/AsciidoctorGradlePluginProject.groovy
+++ b/buildSrc/src/main/groovy/AsciidoctorGradlePluginProject.groovy
@@ -16,6 +16,8 @@ class AsciidoctorGradlePluginProject implements Plugin<Project> {
         project.pluginManager.identity {
             apply 'maven-publish'
             apply 'groovy-gradle-plugin'
+            apply 'java-gradle-plugin'
+            apply 'com.gradle.plugin-publish'
             apply AsciidoctorGradleGroovyProject
         }
 
diff --git a/buildSrc/src/main/groovy/AsciidoctorGradleProjectExtension.groovy b/buildSrc/src/main/groovy/AsciidoctorGradleProjectExtension.groovy
index bb5f5ff07..ee7216698 100644
--- a/buildSrc/src/main/groovy/AsciidoctorGradleProjectExtension.groovy
+++ b/buildSrc/src/main/groovy/AsciidoctorGradleProjectExtension.groovy
@@ -1,6 +1,11 @@
+import com.gradle.publish.PluginBundleExtension
 import groovy.transform.CompileStatic
 import org.gradle.api.Project
 import org.gradle.api.artifacts.ConfigurationContainer
+import org.gradle.api.plugins.ExtensionContainer
+import org.gradle.api.provider.Provider
+import org.gradle.plugin.devel.GradlePluginDevelopmentExtension
+import org.gradle.plugin.devel.PluginDeclaration
 import org.gradle.plugin.devel.tasks.PluginUnderTestMetadata
 import org.ysb33r.grolifant.api.core.ProjectOperations
 
@@ -9,10 +14,19 @@ class AsciidoctorGradleProjectExtension {
 
     private final ProjectOperations projectOperations
     private final ConfigurationContainer configurations
+    private final ExtensionContainer extensions
+    private final Provider<String> pluginExtraTextProvider
 
     AsciidoctorGradleProjectExtension(Project project) {
         this.projectOperations = ProjectOperations.find(project)
         this.configurations = project.configurations
+        this.extensions = project.extensions
+
+        this.pluginExtraTextProvider = projectOperations.versionProvider.map { version ->
+            (version.contains('-alpha') || version.contains('-beta')) ?
+                    ". (If you need a production-ready version of the AsciidoctorJ plugin for Gradle use a 3.x release of this plugin instead)."
+                    : ''
+        }
     }
 
     void withOfflineTestConfigurations() {
@@ -47,4 +61,29 @@ class AsciidoctorGradleProjectExtension {
                 projectOperations.atConfigurationTime()
         ).get()
     }
+
+    void configurePlugin(
+            String pluginId,
+            String providedDisplayName,
+            String providedDescription,
+            String implClass,
+            List<String> providedTags
+    ) {
+        final gradlePlugin = extensions.getByType(GradlePluginDevelopmentExtension)
+        final pluginBundle = extensions.getByType(PluginBundleExtension)
+        final providedName = "${pluginId.replaceAll(~/\./, '')}Plugin".toString()
+        final extraText = pluginExtraTextProvider.get()
+        gradlePlugin.plugins.create(providedName) { PluginDeclaration pd ->
+            pd.tap {
+                id = pluginId
+                displayName = providedDisplayName
+                description = extraText ? "${providedDescription}. ${extraText}" : "${extraText}."
+                implementationClass = implClass
+            }
+        }
+        if (pluginBundle.pluginTags.isEmpty()) {
+            pluginBundle.pluginTags = [(providedName): (Collection<String>)(['asciidoctor'] + providedTags)]
+        }
+        pluginBundle.pluginTags.putAll([(providedName): (['asciidoctor'] + providedTags)])
+    }
 }
diff --git a/docs/src/docs/asciidoc/index.adoc b/docs/src/docs/asciidoc/index.adoc
index 628a8e4a7..a8b39ede8 100644
--- a/docs/src/docs/asciidoc/index.adoc
+++ b/docs/src/docs/asciidoc/index.adoc
@@ -27,7 +27,7 @@ include::parts/asciidoctorj-epub-plugin.adoc[]
 
 include::parts/asciidoctorj-revealjs-plugin.adoc[]
 
-include::parts/asciidoctorj-leanpub-plugin.adoc[]
+// include::parts/asciidoctorj-leanpub-plugin.adoc[]
 
 include::parts/asciidoctor-diagram.adoc[]
 
diff --git a/gems/build.gradle b/gems/build.gradle
index 4c563efa6..a297434e4 100644
--- a/gems/build.gradle
+++ b/gems/build.gradle
@@ -1,30 +1,32 @@
+import org.ysb33r.gradle.gradletest.GradleTest
+
+agProject {
+    configurePlugin 'org.asciidoctor.jvm.gems',
+            'Simplifies support for using external GEMs with AsciidoctorJ',
+            'Provides appropriate tasks and configurations for adding GEMs to AsciidoctorJ conversions',
+            'org.asciidoctor.gradle.jvm.gems.AsciidoctorGemSupportPlugin',
+            ['asciidoctorj', 'gems', 'jruby']
+}
 
 dependencies {
-    implementation "com.github.jruby-gradle:jruby-gradle-core-plugin:${jrubyGradleVersion}"
+    implementation "org.ysb33r.gradle.jruby:jrubygradle-resolver:${pluginJrubySimpleVersion}"
     api project(':asciidoctor-gradle-jvm')
 }
 
-test {
+tasks.named('test', Test) {
     dependsOn ':testfixtures-offline-repo:buildOfflineRepositories'
     systemProperties OFFLINE_REPO: offlineRepoRoot.absolutePath
 }
 
-gradleTest {
+tasks.named('gradleTest', GradleTest) {
 //    gradleArguments '-d'
-    if(OS.windows) {
+    if (OS.windows) {
         // Expecting external-gems to fail due to JRuby issue
         expectFailure ~/external-gems/
     }
 
-    gradleArguments '-d'
-
     // TODO: Re-enable this test
-    enabled = false
-    println "************ :asciidoctor-gradle-jvm-gems:gradleTest is disabled due to potential bug in asciidoctorj  *********"
+//    enabled = false
+//    println "************ :asciidoctor-gradle-jvm-gems:gradleTest is disabled due to potential bug in asciidoctorj  *********"
 }
 
-configurePlugin 'org.asciidoctor.jvm.gems',
-    'Simplifies support for using external GEMs with AsciidoctorJ',
-    'Provides appropriate tasks and configurations for adding GEMs to AsciidoctorJ conversions',
-    [ 'asciidoctorj', 'gems', 'jruby']
-
diff --git a/gems/src/gradleTest/external-gems/build.gradle b/gems/src/gradleTest/external-gems/build.gradle
index c5a24ebd2..6bd634747 100644
--- a/gems/src/gradleTest/external-gems/build.gradle
+++ b/gems/src/gradleTest/external-gems/build.gradle
@@ -18,12 +18,8 @@ dependencies {
     }
 }
 
-asciidoctorj {
-    requires 'asciidoctor-bibtex'
-}
-
 asciidoctor {
-    dependsOn asciidoctorGemsPrepare
+    withGemJar 'asciidoctorGemsJar'
 
     secondarySources {
         include 'biblio.bib'
@@ -34,6 +30,6 @@ asciidoctor {
 // end::use-gems[]
 
 task runGradleTest {
-    dependsOn asciidoctor
+    dependsOn 'asciidoctor'
 }
 
diff --git a/gems/src/intTest/groovy/org/asciidoctor/gradle/jvm/gems/AsciidoctorGemPrepareTaskCachingFunctionalSpec.groovy b/gems/src/intTest/groovy/org/asciidoctor/gradle/jvm/gems/AsciidoctorGemPrepareTaskCachingFunctionalSpec.groovy
index f36aae8ce..b8ef8fc50 100644
--- a/gems/src/intTest/groovy/org/asciidoctor/gradle/jvm/gems/AsciidoctorGemPrepareTaskCachingFunctionalSpec.groovy
+++ b/gems/src/intTest/groovy/org/asciidoctor/gradle/jvm/gems/AsciidoctorGemPrepareTaskCachingFunctionalSpec.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,11 +16,14 @@
 package org.asciidoctor.gradle.jvm.gems
 
 import org.asciidoctor.gradle.jvm.gems.internal.FunctionalSpecification
-import org.asciidoctor.gradle.testfixtures.CachingTest
+import org.asciidoctor.gradle.testfixtures.BuildScanFixture
+import org.asciidoctor.gradle.testfixtures.CachingTestFixture
 import spock.lang.Issue
 import spock.lang.Timeout
 
-class AsciidoctorGemPrepareTaskCachingFunctionalSpec extends FunctionalSpecification implements CachingTest {
+class AsciidoctorGemPrepareTaskCachingFunctionalSpec extends FunctionalSpecification
+        implements CachingTestFixture, BuildScanFixture {
+
     private static final String DEFAULT_TASK = 'asciidoctorGemsPrepare'
     private static final String OUTPUT_DIR_PATH = 'build/.asciidoctorGems'
     private static final String DEFAULT_GEM_NAME = 'asciidoctor-revealjs'
@@ -136,23 +139,22 @@ class AsciidoctorGemPrepareTaskCachingFunctionalSpec extends FunctionalSpecifica
 
     @Override
     File getBuildFile(String extraContent) {
-        File buildFile = testProjectDir.newFile('build.gradle')
-        buildFile << """
-            plugins {
-                id 'org.asciidoctor.jvm.gems'
+        writeGroovyBuildFile(
+                'org.asciidoctor.jvm.gems',
+                extraContent
+        ).withWriterAppend { w ->
+            if (performBuildScan) {
+                w.println(buildScanConfiguration)
             }
 
-            ${ -> scan ? buildScanConfiguration : '' }
-            ${offlineRepositories}
-
+            w.println '''
             repositories {
                 ruby {
                     gems()
                 }
             }
-
-           ${extraContent}
-        """
+            '''.stripIndent()
+        }
         buildFile
     }
 
diff --git a/gems/src/intTest/groovy/org/asciidoctor/gradle/jvm/gems/internal/FunctionalSpecification.groovy b/gems/src/intTest/groovy/org/asciidoctor/gradle/jvm/gems/internal/FunctionalSpecification.groovy
index 27f2e304b..9fb6780bb 100644
--- a/gems/src/intTest/groovy/org/asciidoctor/gradle/jvm/gems/internal/FunctionalSpecification.groovy
+++ b/gems/src/intTest/groovy/org/asciidoctor/gradle/jvm/gems/internal/FunctionalSpecification.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,55 +16,51 @@
 package org.asciidoctor.gradle.jvm.gems.internal
 
 import org.apache.commons.io.FileUtils
+import org.asciidoctor.gradle.testfixtures.FunctionalTestFixture
 import org.gradle.testkit.runner.GradleRunner
-import org.junit.Rule
-import org.junit.rules.TemporaryFolder
 import org.ysb33r.grolifant.api.core.OperatingSystem
 import spock.lang.Specification
+import spock.lang.TempDir
 
-class FunctionalSpecification extends Specification {
+class FunctionalSpecification extends Specification implements FunctionalTestFixture {
     public static final String TEST_PROJECTS_DIR = System.getProperty(
-        'TEST_PROJECTS_DIR',
-        './asciidoctor-gradle-jvm-gems/src/intTest/projects'
+            'TEST_PROJECTS_DIR',
+            './asciidoctor-gradle-jvm-gems/src/intTest/projects'
     )
     public static final String TEST_REPO_DIR = System.getProperty(
-        'OFFLINE_REPO',
-        './testfixtures/offline-repo/build/repo'
+            'OFFLINE_REPO',
+            './testfixtures/offline-repo/build/repo'
     )
     public static final OperatingSystem OS = OperatingSystem.current()
 
-    @Rule
-    TemporaryFolder testProjectDir
+    @TempDir
+    File testProjectDir
 
-    @Rule
-    TemporaryFolder alternateProjectDir
-
-    GradleRunner getGradleRunner(List<String> taskNames) {
-        GradleRunner.create()
-            .withProjectDir(testProjectDir.root)
-            .withArguments(taskNames)
-            .withPluginClasspath()
-            .forwardOutput()
-            .withDebug(true)
+    void setup() {
+        projectDir.mkdirs()
     }
 
-    @SuppressWarnings(['BuilderMethodWithSideEffects'])
-    void createTestProject(String docGroup) {
-        FileUtils.copyDirectory(new File(TEST_PROJECTS_DIR, docGroup), testProjectDir.root)
+    GradleRunner getGradleRunner(List<String> taskNames) {
+        getGroovyGradleRunner(taskNames)
     }
 
-    String getOfflineRepositories() {
-        File repo = new File(TEST_REPO_DIR, 'repositories.gradle')
-        if (!repo.exists()) {
-            throw new FileNotFoundException(
-                "${repo} not found. Run ':testfixture-offline-repo:buildOfflineRepositories' build task"
-            )
-        }
+//    @SuppressWarnings(['BuilderMethodWithSideEffects'])
+//    void createTestProject(String docGroup) {
+//        FileUtils.copyDirectory(new File(TEST_PROJECTS_DIR, docGroup), projectDir)
+//    }
 
-        if (OS.windows) {
-            "apply from: /${repo.absolutePath}/"
-        } else {
-            "apply from: '${repo.absolutePath}'"
-        }
-    }
+//    String getOfflineRepositories() {
+//        File repo = new File(TEST_REPO_DIR, 'repositories.gradle')
+//        if (!repo.exists()) {
+//            throw new FileNotFoundException(
+//                    "${repo} not found. Run ':testfixture-offline-repo:buildOfflineRepositories' build task"
+//            )
+//        }
+//
+//        if (OS.windows) {
+//            "apply from: /${repo.absolutePath}/"
+//        } else {
+//            "apply from: '${repo.absolutePath}'"
+//        }
+//    }
 }
\ No newline at end of file
diff --git a/gems/src/main/groovy/org/asciidoctor/gradle/jvm/gems/AsciidoctorGemPrepare.groovy b/gems/src/main/groovy/org/asciidoctor/gradle/jvm/gems/AsciidoctorGemPrepare.groovy
index 932e1c751..14907b9f5 100644
--- a/gems/src/main/groovy/org/asciidoctor/gradle/jvm/gems/AsciidoctorGemPrepare.groovy
+++ b/gems/src/main/groovy/org/asciidoctor/gradle/jvm/gems/AsciidoctorGemPrepare.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,48 +15,38 @@
  */
 package org.asciidoctor.gradle.jvm.gems
 
-import com.github.jrubygradle.api.core.AbstractJRubyPrepare
 import groovy.transform.CompileStatic
 import org.asciidoctor.gradle.jvm.AsciidoctorJExtension
-import org.gradle.api.provider.Provider
 import org.gradle.api.tasks.CacheableTask
+import org.gradle.workers.WorkerExecutor
+import org.ysb33r.gradle.jruby.api.tasks.AbstractGemPrepareTask
 
+import javax.inject.Inject
 import java.util.concurrent.Callable
 
-import static com.github.jrubygradle.api.gems.GemUtils.JRUBY_ARCHIVE_NAME
-
-/** Prepare additional GEMs for AsciidoctorJ.
+/**
+ * Prepare additional GEMs for AsciidoctorJ.
  *
  * @since 2.0
  */
 @CacheableTask
 @CompileStatic
-class AsciidoctorGemPrepare extends AbstractJRubyPrepare {
+class AsciidoctorGemPrepare extends AbstractGemPrepareTask {
 
-    /** Location of {@code jruby-complete} JAR.
-     *
-     * @return Path on local filesystem
-     */
-    @Override
-    protected Provider<File> getJrubyJarLocation() {
-        project.provider({ AsciidoctorJExtension jruby ->
-            jruby.configuration.files.find { it.name.startsWith(JRUBY_ARCHIVE_NAME) }
-        }.curry(jruby) as Callable<File>)
-    }
+//    private final Provider<File> jrubyJarLocationProvider
+    private final AsciidoctorJExtension jruby
 
-    /** Version of JRuby that will be used if explicitly set
-     *
-     * This method does not resolve any files to obtain the version.
-     *
-     * @return Explicitly configured project global version of JRuby or
-     * {@code null} if inferred from the asciidoctorj dependency.
-     */
-    @Override
-    protected String getProposedJRubyVersion() {
-        jruby.jrubyVersion
-    }
+    @Inject
+    @SuppressWarnings('UnnecessarySetter')
+    AsciidoctorGemPrepare(WorkerExecutor we) {
+        super(we)
+        this.jruby = project.extensions.getByType(AsciidoctorJExtension)
+        setJrubyJarProvider(project.provider({ AsciidoctorJExtension jruby ->
+            jruby.configuration.files.find { it.name.startsWith(JRUBY_COMPLETE_NAME) }
+        }.curry(jruby) as Callable<File>))
 
-    private AsciidoctorJExtension getJruby() {
-        project.extensions.getByType(AsciidoctorJExtension)
+//        this.jrubyJarLocationProvider = project.provider({ AsciidoctorJExtension jruby ->
+//            jruby.configuration.files.find { it.name.startsWith(JRUBY_ARCHIVE_NAME) }
+//        }.curry(jruby) as Callable<File>)
     }
 }
diff --git a/gems/src/main/groovy/org/asciidoctor/gradle/jvm/gems/AsciidoctorGemSupportPlugin.groovy b/gems/src/main/groovy/org/asciidoctor/gradle/jvm/gems/AsciidoctorGemSupportPlugin.groovy
index da548ace8..8162fe9d6 100644
--- a/gems/src/main/groovy/org/asciidoctor/gradle/jvm/gems/AsciidoctorGemSupportPlugin.groovy
+++ b/gems/src/main/groovy/org/asciidoctor/gradle/jvm/gems/AsciidoctorGemSupportPlugin.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,17 +15,15 @@
  */
 package org.asciidoctor.gradle.jvm.gems
 
-import com.github.jrubygradle.api.core.JRubyCorePlugin
 import groovy.transform.CompileStatic
 import org.asciidoctor.gradle.jvm.AsciidoctorJBasePlugin
-import org.asciidoctor.gradle.jvm.AsciidoctorJExtension
 import org.gradle.api.Action
 import org.gradle.api.Plugin
 import org.gradle.api.Project
 import org.gradle.api.artifacts.Configuration
-import org.ysb33r.grolifant.api.v4.TaskProvider
-
-import static org.ysb33r.grolifant.api.v4.TaskProvider.registerTask
+import org.gradle.api.tasks.bundling.Jar
+import org.ysb33r.gradle.jruby.api.plugins.JRubyResolverPlugin
+import org.ysb33r.grolifant.api.core.ProjectOperations
 
 /** Plugin that simplifies that management of external GEMs.
  *
@@ -44,19 +42,25 @@ import static org.ysb33r.grolifant.api.v4.TaskProvider.registerTask
 class AsciidoctorGemSupportPlugin implements Plugin<Project> {
 
     public static final String GEM_CONFIGURATION = 'asciidoctorGems'
-    public static final String GEMPREP_TASK = 'asciidoctorGemsPrepare'
+    public static final String GEMPREP_TASK = "${GEM_CONFIGURATION}Prepare"
+    public static final String JAR_TASK = "${GEM_CONFIGURATION}Jar"
 
     @Override
     void apply(Project project) {
-        project.apply plugin: AsciidoctorJBasePlugin
-        project.apply plugin: JRubyCorePlugin
+        project.pluginManager.tap {
+            apply AsciidoctorJBasePlugin
+            apply JRubyResolverPlugin
+        }
+        final po = ProjectOperations.find(project)
         Configuration gemConfig = project.configurations.maybeCreate(GEM_CONFIGURATION)
+        gemConfig.canBeResolved = true
+        gemConfig.canBeConsumed = false
 
         Action gemPrepDefaults = new Action<AsciidoctorGemPrepare>() {
             @Override
             void execute(AsciidoctorGemPrepare asciidoctorGemPrepare) {
-                asciidoctorGemPrepare.with {
-                    dependencies gemConfig
+                asciidoctorGemPrepare.tap {
+                    gemConfiguration = gemConfig
                     group = 'dependencies'
                     description = 'Prepare additional GEMs for AsciidoctorJ'
                     outputDir = "${project.buildDir}/.asciidoctorGems"
@@ -64,12 +68,23 @@ class AsciidoctorGemSupportPlugin implements Plugin<Project> {
             }
         }
 
-        TaskProvider<AsciidoctorGemPrepare> prepTask = registerTask(
-            project,
-            GEMPREP_TASK,
-            AsciidoctorGemPrepare,
-            gemPrepDefaults
+        final prepTask = project.tasks.register(
+                GEMPREP_TASK,
+                AsciidoctorGemPrepare,
+                gemPrepDefaults
         )
-        project.extensions.getByType(AsciidoctorJExtension).gemPaths { prepTask.get().outputDir }
+
+        project.tasks.register(JAR_TASK, Jar) { jar ->
+            jar.tap {
+                from(prepTask.map { it.outputDir })
+                archiveFileName.set("${GEM_CONFIGURATION}.jar".toString())
+                destinationDirectory.set(
+                        project.objects
+                                .directoryProperty()
+                                .fileProvider(po.buildDirDescendant('.asciidoctorGemsJars'))
+                )
+                dependsOn(prepTask)
+            }
+        }
     }
 }
diff --git a/gems/src/main/resources/META-INF/gradle-plugins/org.asciidoctor.jvm.gems.properties b/gems/src/main/resources/META-INF/gradle-plugins/org.asciidoctor.jvm.gems.properties
deleted file mode 100644
index 104a2e15a..000000000
--- a/gems/src/main/resources/META-INF/gradle-plugins/org.asciidoctor.jvm.gems.properties
+++ /dev/null
@@ -1,17 +0,0 @@
-#
-# Copyright 2013-2023 the original author or 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
-#
-#     http://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.
-#
-
-implementation-class=org.asciidoctor.gradle.jvm.gems.AsciidoctorGemSupportPlugin
diff --git a/gems/src/test/groovy/org/asciidoctor/gradle/jvm/gems/AsciidoctorGemSupportPluginSpec.groovy b/gems/src/test/groovy/org/asciidoctor/gradle/jvm/gems/AsciidoctorGemSupportPluginSpec.groovy
index d2fa75b6e..664d7db6b 100644
--- a/gems/src/test/groovy/org/asciidoctor/gradle/jvm/gems/AsciidoctorGemSupportPluginSpec.groovy
+++ b/gems/src/test/groovy/org/asciidoctor/gradle/jvm/gems/AsciidoctorGemSupportPluginSpec.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -33,7 +33,6 @@ class AsciidoctorGemSupportPluginSpec extends Specification {
 
         then:
         project.configurations.getByName(GEM_CONFIGURATION)
-        project.tasks.getByName(GEMPREP_TASK).outputDir == project.file( "${project.buildDir}/.asciidoctorGems" )
-        !project.tasks.getByName(GEMPREP_TASK).dependencies.empty
+        project.tasks.getByName(GEMPREP_TASK).outputDir.get() == project.file( "${project.buildDir}/.asciidoctorGems" )
     }
 }
\ No newline at end of file
diff --git a/gradle.properties b/gradle.properties
index 369371951..b6200eee1 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -14,10 +14,10 @@ jsoupVersion           = 1.13.1
 spockVersion           = 2.3-groovy-3.0
 grolifantVersion       = 2.2.1
 jacocoVersion          = 0.8.6
-jrubyGradleVersion     = 2.0.2
 codenarcVersion        = 3.3.0
 nodejsGradleVersion    = 2.2.0
-pluginJrubySimpleVersion = 1.0.0-alpha.1
+pluginJrubySimpleVersion = 1.0.0-alpha.2-SNAPSHOT
+pluginPublishPlugin = 1.2.1
 
 org.gradle.daemon   = true
 org.gradle.parallel = true
diff --git a/gradle/gradle-plugin-dependencies.gradle b/gradle/gradle-plugin-dependencies.gradle
index 61212a03d..879304514 100644
--- a/gradle/gradle-plugin-dependencies.gradle
+++ b/gradle/gradle-plugin-dependencies.gradle
@@ -7,7 +7,7 @@ dependencies {
         exclude group: 'org.hamcrest', module: 'hamcrest-core'
     }
 
-    if(configurations.findByName('intTestCompile')) {
+    if (configurations.findByName('intTestCompile')) {
         intTestImplementation project(':testfixtures-jvm')
         intTestImplementation("org.spockframework:spock-core:$spockVersion") {
             exclude group: 'org.codehaus.groovy'
@@ -15,3 +15,4 @@ dependencies {
         }
     }
 }
+
diff --git a/gradle/integration-tests.gradle b/gradle/integration-tests.gradle
index b6fe11c74..16f30260f 100644
--- a/gradle/integration-tests.gradle
+++ b/gradle/integration-tests.gradle
@@ -1,14 +1,17 @@
+
 sourceSets {
     intTest
 }
 
 configurations {
-    intTestOfflineRepo
+    intTestOfflineRepo {
+        canBeConsumed = false
+        canBeResolved = true
+    }
 }
 
-
 // For a single test, you can run "gradle intTest --tests <test name> "
-task intTest(type: Test) {
+tasks.register('intTest', Test) {
     description = "Runs the plugin's integration tests"
     group = "verification"
 
@@ -20,17 +23,18 @@ task intTest(type: Test) {
     classpath = sourceSets.intTest.runtimeClasspath
 
     dependsOn ':testfixtures-offline-repo:buildOfflineRepositories'
-    systemProperties OFFLINE_REPO: offlineRepoRoot.absolutePath
+    systemProperties OFFLINE_REPO: offlineRepoRoot.absolutePath,
+            TEST_PROJECTS_DIR: file('src/intTest/projects')
 }
 
-check {
-    dependsOn intTest
+tasks.named('check') {
+    dependsOn 'intTest'
 }
 
 pluginManager.withPlugin('jacoco') {
     jacocoTestReport {
-        executionData intTest
-        mustRunAfter intTest
+        executionData tasks.intTest
+        mustRunAfter 'intTest'
     }
 }
 
diff --git a/gradle/publishing.gradle b/gradle/publishing.gradle
index 8424491ea..e834fee2a 100644
--- a/gradle/publishing.gradle
+++ b/gradle/publishing.gradle
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-apply plugin: 'java-gradle-plugin'
-apply plugin: 'com.gradle.plugin-publish'
+//apply plugin: 'java-gradle-plugin'
+//apply plugin: 'com.gradle.plugin-publish'
 
 ext {
     pluginIdPrefix = 'org.asciidoctor'
diff --git a/js/build.gradle b/js/build.gradle
index fdd118c23..6a6b440a8 100644
--- a/js/build.gradle
+++ b/js/build.gradle
@@ -79,6 +79,7 @@ tasks.withType(Test).configureEach {
     systemProperties 'org.ysb33r.gradle.nodejs.uri': file(nodejsCacheDir).absoluteFile.toURI()
 }
 
+// TODO: Use configurePlugin instead
 gradlePlugin {
     plugins {
         basePlugin {
diff --git a/js/src/intTest/groovy/org/asciidoctor/gradle/js/nodejs/internal/FunctionalSpecification.groovy b/js/src/intTest/groovy/org/asciidoctor/gradle/js/nodejs/internal/FunctionalSpecification.groovy
index 4b4777744..6758c0c7f 100644
--- a/js/src/intTest/groovy/org/asciidoctor/gradle/js/nodejs/internal/FunctionalSpecification.groovy
+++ b/js/src/intTest/groovy/org/asciidoctor/gradle/js/nodejs/internal/FunctionalSpecification.groovy
@@ -15,21 +15,16 @@
  */
 package org.asciidoctor.gradle.js.nodejs.internal
 
-import groovy.transform.CompileStatic
 import org.apache.commons.io.FileUtils
 import org.asciidoctor.gradle.testfixtures.DslType
 import org.asciidoctor.gradle.testfixtures.FunctionalTestFixture
-import org.asciidoctor.gradle.testfixtures.FunctionalTestSetup
-import org.gradle.testkit.runner.GradleRunner
 import spock.lang.Specification
 import spock.lang.TempDir
 
 import static org.asciidoctor.gradle.testfixtures.DslType.GROOVY_DSL
 import static org.asciidoctor.gradle.testfixtures.DslType.KOTLIN_DSL
-import static org.asciidoctor.gradle.testfixtures.FunctionalTestSetup.getOfflineRepositoriesGroovyDsl
-import static org.asciidoctor.gradle.testfixtures.FunctionalTestSetup.getOfflineRepositoriesKotlinDsl
 
-class FunctionalSpecification extends Specification implements FunctionalTestFixture{
+class FunctionalSpecification extends Specification implements FunctionalTestFixture {
 
     public static final String TEST_PROJECTS_DIR = System.getProperty(
             'TEST_PROJECTS_DIR',
@@ -39,7 +34,6 @@ class FunctionalSpecification extends Specification implements FunctionalTestFix
     @TempDir
     File testProjectDir
 
-
     void setup() {
         initializeProjectLayout()
     }
diff --git a/jvm-epub/build.gradle b/jvm-epub/build.gradle
index 572c788ec..1225dbb18 100644
--- a/jvm-epub/build.gradle
+++ b/jvm-epub/build.gradle
@@ -1,10 +1,22 @@
+agProject {
+    withOfflineTestConfigurations()
+
+    configurePlugin(
+            'org.asciidoctor.jvm.epub',
+            'AsciidoctorJ EPUB Plugin',
+            'Asciidoctor task for creating EPUB3 documents',
+            'org.asciidoctor.gradle.jvm.epub.AsciidoctorJEpubPlugin',
+            ['asciidoctorj', 'epub', 'epub3']
+    )
+}
+
 generateModuleVersions {
     basename = 'asciidoctorj-epub'
     propertyNames ~/^kindlegen$/
 }
 
 dependencies {
-    compile project(':asciidoctor-gradle-jvm')
+    implementation project(':asciidoctor-gradle-jvm')
 
     intTestOfflineRepo "org.asciidoctor:asciidoctorj:${compileOnlyAsciidoctorJVersion}"
     intTestOfflineRepo "org.asciidoctor:asciidoctorj-epub3:${downloadOnlyEpubVersion}"
@@ -13,14 +25,3 @@ dependencies {
 intTest {
     systemProperties TEST_PROJECTS_DIR: file('src/intTest/projects')
 }
-
-configurePlugin 'org.asciidoctor.jvm.epub',
-        'AsciidoctorJ EPUB Plugin',
-        'Asciidoctor task for creating EPUB3 documents',
-        ['asciidoctorj', 'epub', 'epub3']
-
-gradleTest {
-// TODO: Re-enable this test
-//    enabled = false
-//    println "************ :asciidoctor-gradle-jvm-epub:gradleTest is disabled due to potential bug in asciidoctorj  *********"
-}
\ No newline at end of file
diff --git a/jvm-epub/src/gradleTest/epub3/build.gradle b/jvm-epub/src/gradleTest/epub3/build.gradle
index 108b2136c..74c8e40b5 100644
--- a/jvm-epub/src/gradleTest/epub3/build.gradle
+++ b/jvm-epub/src/gradleTest/epub3/build.gradle
@@ -12,7 +12,7 @@ asciidoctorEpub {
         include 'epub3.adoc'
     }
 
-    inProcess IN_PROCESS
+    executionMode = IN_PROCESS
 }
 
 task runGradleTest {
diff --git a/jvm-epub/src/gradleTest/issue-409-link-regression/src/docs/asciidoc/chapter1.adoc b/jvm-epub/src/gradleTest/issue-409-link-regression/src/docs/asciidoc/chapter1.adoc
deleted file mode 100644
index 202e1d8f7..000000000
--- a/jvm-epub/src/gradleTest/issue-409-link-regression/src/docs/asciidoc/chapter1.adoc
+++ /dev/null
@@ -1,6 +0,0 @@
-[[chapter1]]
-= Chapter 1
-
-Some text.
-
-<<chapter2.adoc#subtitle,Link to subtitle in chapter 2>>
diff --git a/jvm-epub/src/gradleTest/issue-409-link-regression/src/docs/asciidoc/chapter2.adoc b/jvm-epub/src/gradleTest/issue-409-link-regression/src/docs/asciidoc/chapter2.adoc
deleted file mode 100644
index 59b93f91c..000000000
--- a/jvm-epub/src/gradleTest/issue-409-link-regression/src/docs/asciidoc/chapter2.adoc
+++ /dev/null
@@ -1,9 +0,0 @@
-[[chapter2]]
-= Chapter 2
-
-Some text.
-
-[[subtitle]]
-== Subtitle
-
-More text.
diff --git a/jvm-epub/src/gradleTest/issue-409-link-regression/src/docs/asciidoc/epub3.adoc b/jvm-epub/src/gradleTest/issue-409-link-regression/src/docs/asciidoc/epub3.adoc
deleted file mode 100644
index 7172f3e25..000000000
--- a/jvm-epub/src/gradleTest/issue-409-link-regression/src/docs/asciidoc/epub3.adoc
+++ /dev/null
@@ -1,6 +0,0 @@
-// Taken from https://github.com/slonopotamus/asciidoc-epub3-link-regression/tree/master/src/docs/asciidoc
-= Project Euler
-:doctype: book
-
-include::chapter1.adoc[leveloffset=+1]
-include::chapter2.adoc[leveloffset=+1]
diff --git a/jvm-epub/src/intTest/groovy/org/asciidoctor/gradle/jvm/epub/AsciidoctorEpubTaskCachingFunctionalSpec.groovy b/jvm-epub/src/intTest/groovy/org/asciidoctor/gradle/jvm/epub/AsciidoctorEpubTaskCachingFunctionalSpec.groovy
index a299c5119..3d69d32e1 100644
--- a/jvm-epub/src/intTest/groovy/org/asciidoctor/gradle/jvm/epub/AsciidoctorEpubTaskCachingFunctionalSpec.groovy
+++ b/jvm-epub/src/intTest/groovy/org/asciidoctor/gradle/jvm/epub/AsciidoctorEpubTaskCachingFunctionalSpec.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,11 +16,13 @@
 package org.asciidoctor.gradle.jvm.epub
 
 import org.asciidoctor.gradle.jvm.epub.internal.FunctionalSpecification
-import org.asciidoctor.gradle.testfixtures.CachingTest
+import org.asciidoctor.gradle.testfixtures.BuildScanFixture
+import org.asciidoctor.gradle.testfixtures.CachingTestFixture
 
 import static org.asciidoctor.gradle.testfixtures.JRubyTestVersions.AJ20_SAFE_MAXIMUM
 
-class AsciidoctorEpubTaskCachingFunctionalSpec extends FunctionalSpecification implements CachingTest {
+class AsciidoctorEpubTaskCachingFunctionalSpec extends FunctionalSpecification
+        implements CachingTestFixture, BuildScanFixture {
     private static final String DEFAULT_TASK = 'asciidoctorEpub'
     private static final String DEFAULT_OUTPUT_FILE = 'build/docs/asciidocEpub/epub3.epub'
     private static final String JRUBY_TEST_VERSION = AJ20_SAFE_MAXIMUM
@@ -59,17 +61,11 @@ class AsciidoctorEpubTaskCachingFunctionalSpec extends FunctionalSpecification i
     }
 
     File getBuildFile(String extraContent) {
-        File buildFile = testProjectDir.newFile('build.gradle')
-        buildFile << """
-            plugins {
-                id 'org.asciidoctor.jvm.epub'
+        writeGroovyBuildFile('org.asciidoctor.jvm.epub', extraContent).withWriterAppend { w ->
+            if (performBuildScan) {
+                w.println buildScanConfiguration
             }
-            
-            ${scan ? buildScanConfiguration : ''}
-            ${offlineRepositories}
-            
-            ${extraContent}
-        """
+        }
         buildFile
     }
 
diff --git a/jvm-epub/src/intTest/groovy/org/asciidoctor/gradle/jvm/epub/AsciidoctorEpubTaskFunctionalSpec.groovy b/jvm-epub/src/intTest/groovy/org/asciidoctor/gradle/jvm/epub/AsciidoctorEpubTaskFunctionalSpec.groovy
index 31c7d98a4..87002866a 100644
--- a/jvm-epub/src/intTest/groovy/org/asciidoctor/gradle/jvm/epub/AsciidoctorEpubTaskFunctionalSpec.groovy
+++ b/jvm-epub/src/intTest/groovy/org/asciidoctor/gradle/jvm/epub/AsciidoctorEpubTaskFunctionalSpec.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -40,7 +40,7 @@ class AsciidoctorEpubTaskFunctionalSpec extends FunctionalSpecification {
 
         then:
         verifyAll {
-            new File(testProjectDir.root, 'build/docs/asciidocEpub/epub3.epub').exists()
+            new File(projectDir, 'build/docs/asciidocEpub/epub3.epub').exists()
             !result.output.contains('include file not found:')
         }
     }
@@ -57,7 +57,7 @@ class AsciidoctorEpubTaskFunctionalSpec extends FunctionalSpecification {
 
         then:
         verifyAll {
-            new File(testProjectDir.root, 'build/docs/asciidocEpub/epub3.mobi').exists()
+            new File(projectDir, 'build/docs/asciidocEpub/epub3.mobi').exists()
             !result.output.contains('include file not found:')
         }
     }
@@ -86,7 +86,7 @@ class AsciidoctorEpubTaskFunctionalSpec extends FunctionalSpecification {
 
         then:
         verifyAll {
-            new File(testProjectDir.root, 'build/docs/asciidocEpub/epub3.epub').exists()
+            new File(projectDir, 'build/docs/asciidocEpub/epub3.epub').exists()
             !result.output.contains('include file not found:')
         }
 
@@ -132,17 +132,6 @@ class AsciidoctorEpubTaskFunctionalSpec extends FunctionalSpecification {
     }
 
     File getBuildFile(String extraContent) {
-        File buildFile = testProjectDir.newFile('build.gradle')
-        buildFile << """
-plugins {
-    id 'org.asciidoctor.jvm.epub'
-}
-
-${offlineRepositories}
-
-${extraContent}
-"""
-        buildFile
+        writeGroovyBuildFile('org.asciidoctor.jvm.epub', extraContent)
     }
-
 }
\ No newline at end of file
diff --git a/jvm-epub/src/intTest/groovy/org/asciidoctor/gradle/jvm/epub/LinkedChaptersFunctionalSpec.groovy b/jvm-epub/src/intTest/groovy/org/asciidoctor/gradle/jvm/epub/LinkedChaptersFunctionalSpec.groovy
index c117b92d9..d49dc44bb 100644
--- a/jvm-epub/src/intTest/groovy/org/asciidoctor/gradle/jvm/epub/LinkedChaptersFunctionalSpec.groovy
+++ b/jvm-epub/src/intTest/groovy/org/asciidoctor/gradle/jvm/epub/LinkedChaptersFunctionalSpec.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -50,24 +50,14 @@ class LinkedChaptersFunctionalSpec extends FunctionalSpecification {
 
         then:
         verifyAll {
-            new File(testProjectDir.root, 'build/docs/asciidocEpub/epub3.epub').exists()
+            new File(projectDir, 'build/docs/asciidocEpub/epub3.epub').exists()
             !result.output.contains('invalid reference to anchor')
             !result.output.contains('invalid reference to unknown anchor')
         }
     }
 
     File getBuildFile(String extraContent) {
-        File buildFile = testProjectDir.newFile('build.gradle')
-        buildFile << """
-plugins {
-    id 'org.asciidoctor.jvm.epub'
-}
-
-${offlineRepositories}
-
-${extraContent}
-"""
-        buildFile
+        writeGroovyBuildFile('org.asciidoctor.jvm.epub', extraContent)
     }
 
 }
\ No newline at end of file
diff --git a/jvm-epub/src/intTest/groovy/org/asciidoctor/gradle/jvm/epub/internal/FunctionalSpecification.groovy b/jvm-epub/src/intTest/groovy/org/asciidoctor/gradle/jvm/epub/internal/FunctionalSpecification.groovy
index 5f5105dac..82e761855 100644
--- a/jvm-epub/src/intTest/groovy/org/asciidoctor/gradle/jvm/epub/internal/FunctionalSpecification.groovy
+++ b/jvm-epub/src/intTest/groovy/org/asciidoctor/gradle/jvm/epub/internal/FunctionalSpecification.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,15 +16,15 @@
 package org.asciidoctor.gradle.jvm.epub.internal
 
 import org.apache.commons.io.FileUtils
+import org.asciidoctor.gradle.testfixtures.FunctionalTestFixture
 import org.asciidoctor.gradle.testfixtures.FunctionalTestSetup
 import org.gradle.testkit.runner.GradleRunner
 import org.gradle.util.VersionNumber
-import org.junit.Rule
-import org.junit.rules.TemporaryFolder
 import org.ysb33r.grolifant.api.core.OperatingSystem
 import spock.lang.Specification
+import spock.lang.TempDir
 
-class FunctionalSpecification extends Specification {
+class FunctionalSpecification extends Specification implements FunctionalTestFixture {
 
     @SuppressWarnings('LineLength')
     static
@@ -34,24 +34,25 @@ class FunctionalSpecification extends Specification {
     static
     final OperatingSystem OS = OperatingSystem.current()
 
-    @Rule
-    TemporaryFolder testProjectDir
+    @TempDir
+    File testProjectDir
 
-    @Rule
-    TemporaryFolder alternateProjectDir
+    void setup() {
+        projectDir.mkdirs()
+    }
 
     GradleRunner getGradleRunner(List<String> taskNames = ['asciidoctor']) {
         GradleRunner.create()
-            .withProjectDir(testProjectDir.root)
-            .withArguments(taskNames)
-            .withPluginClasspath()
-            .forwardOutput()
-            .withDebug(true)
+                .withProjectDir(projectDir)
+                .withArguments(taskNames)
+                .withPluginClasspath()
+                .forwardOutput()
+                .withDebug(true)
     }
 
     @SuppressWarnings(['BuilderMethodWithSideEffects'])
     void createTestProject(String docGroup = 'epub3') {
-        FileUtils.copyDirectory(new File(TEST_PROJECTS_DIR, docGroup), testProjectDir.root)
+        FileUtils.copyDirectory(new File(TEST_PROJECTS_DIR, docGroup), projectDir)
     }
 
     @SuppressWarnings('LineLength')
@@ -68,8 +69,8 @@ class FunctionalSpecification extends Specification {
         }
     }
 
-    static boolean isWindowsOr64bitOnlyMacOS() {
-        VersionNumber version = VersionNumber.parse(OS.version)
-        OS.windows || (OS.macOsX && version.major >= 10 && version.minor >= 15)
-    }
+//    static boolean isWindowsOr64bitOnlyMacOS() {
+//        VersionNumber version = VersionNumber.parse(OS.version)
+//        OS.windows || (OS.macOsX && version.major >= 10 && version.minor >= 15)
+//    }
 }
\ No newline at end of file
diff --git a/jvm-epub/src/main/groovy/org/asciidoctor/gradle/jvm/epub/AsciidoctorEpubTask.groovy b/jvm-epub/src/main/groovy/org/asciidoctor/gradle/jvm/epub/AsciidoctorEpubTask.groovy
index 17b7be0e0..604ee2dd4 100644
--- a/jvm-epub/src/main/groovy/org/asciidoctor/gradle/jvm/epub/AsciidoctorEpubTask.groovy
+++ b/jvm-epub/src/main/groovy/org/asciidoctor/gradle/jvm/epub/AsciidoctorEpubTask.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,20 +19,19 @@ import groovy.transform.CompileDynamic
 import groovy.transform.CompileStatic
 import org.asciidoctor.gradle.base.AsciidoctorExecutionException
 import org.asciidoctor.gradle.base.Transform
-import org.asciidoctor.gradle.base.process.ProcessMode
 import org.asciidoctor.gradle.internal.ExecutorConfiguration
 import org.asciidoctor.gradle.jvm.AbstractAsciidoctorTask
 import org.gradle.api.tasks.CacheableTask
 import org.gradle.api.tasks.Input
 import org.gradle.api.tasks.util.PatternSet
-import org.gradle.util.GradleVersion
 import org.gradle.workers.WorkerExecutor
 import org.ysb33r.grolifant.api.core.Version
 
 import javax.inject.Inject
 import java.util.regex.Matcher
 
-/** Builds EPUB documents using the epub3 backend.
+/**
+ * Builds EPUB documents using the epub3 backend.
  *
  * @author Schalk W. Cronjé
  * @author Gary Hale
@@ -44,22 +43,21 @@ import java.util.regex.Matcher
 class AsciidoctorEpubTask extends AbstractAsciidoctorTask {
 
     public static final String EPUB3 = 'epub3'
-
     private static final String BACKEND = 'epub3'
     private static final String EBOOK_FORMAT_ATTR = 'ebook-format'
-
     private final Set<String> ebookFormats = []
 
     @Inject
     AsciidoctorEpubTask(WorkerExecutor we) {
         super(we)
 
-        configuredOutputOptions.backends = [BACKEND]
+        outputOptions.backends = [BACKEND]
         copyNoResources()
-        inProcess = JAVA_EXEC
+//        inProcess = JAVA_EXEC
     }
 
-    /** The eBook formats that needs to be generated.
+    /**
+     * The eBook formats that needs to be generated.
      *
      * @return eBook formats that needs to be generated.
      */
@@ -68,7 +66,8 @@ class AsciidoctorEpubTask extends AbstractAsciidoctorTask {
         this.ebookFormats
     }
 
-    /** Resets the list of formats that needs to be generated
+    /**
+     * Resets the list of formats that needs to be generated
      *
      * Any format supported by asciidoctorj-epub can be listed here.
      * This method will overide any {@code ebook-format} that is set via {@link #attributes}.
@@ -82,7 +81,8 @@ class AsciidoctorEpubTask extends AbstractAsciidoctorTask {
         this.ebookFormats.addAll(Transform.toSet(formats) { String it -> it.toLowerCase() } as Set<String>)
     }
 
-    /** Adds aditional eBook formats
+    /**
+     * Adds aditional eBook formats
      *
      * @param formats List of formats. The plugin does not verify whether the eBook format
      *  is valid.
@@ -91,29 +91,31 @@ class AsciidoctorEpubTask extends AbstractAsciidoctorTask {
         this.ebookFormats.addAll(formats*.toLowerCase() as List)
     }
 
-    /** The default pattern set for secondary sources.
+    /**
+     * The default pattern set for secondary sources.
      *
      * @return {@link #getDefaultSourceDocumentPattern} + `*docinfo*`.
      */
     @Override
-    protected PatternSet getDefaultSecondarySourceDocumentPattern() {
+    PatternSet getDefaultSecondarySourceDocumentPattern() {
         defaultSourceDocumentPattern
     }
 
-    /** Returns all of the executor configurations for this task
+    /**
+     * Returns all of the executor configurations for this task
      *
      * @return Executor configurations
      */
     @Override
     protected Map<String, ExecutorConfiguration> getExecutorConfigurations(
-        File workingSourceDir,
-        Set<File> sourceFiles,
-        Optional<String> lang
+            File workingSourceDir,
+            Set<File> sourceFiles,
+            Optional<String> lang
     ) {
         Map<String, ExecutorConfiguration> executorConfigurations = super.getExecutorConfigurations(
-            workingSourceDir,
-            sourceFiles,
-            lang
+                workingSourceDir,
+                sourceFiles,
+                lang
         )
 
         final Closure<String> backendName = { String fmt ->
@@ -147,23 +149,23 @@ class AsciidoctorEpubTask extends AbstractAsciidoctorTask {
         }
     }
 
-    /** Selects a final process mode.
-     *
-     * Selects JAVA_EXEC on any Gradle version that has classpath ;eakage issues.
-     *
-     * @return Process mode to use for execution.
-     */
-    @Override
-    protected ProcessMode getFinalProcessMode() {
-        if (GradleVersion.current() <= LAST_GRADLE_WITH_CLASSPATH_LEAKAGE) {
-            if (inProcess != JAVA_EXEC) {
-                logger.warn 'EPUB processing on this version of Gradle will fail due to classpath issues. ' +
-                    'Switching to JAVA_EXEC instead.'
-            }
-            return JAVA_EXEC
-        }
-        super.finalProcessMode
-    }
+//    /** Selects a final process mode.
+//     *
+//     * Selects JAVA_EXEC on any Gradle version that has classpath ;eakage issues.
+//     *
+//     * @return Process mode to use for execution.
+//     */
+//    @Override
+//    protected ProcessMode getFinalProcessMode() {
+//        if (GradleVersion.current() <= LAST_GRADLE_WITH_CLASSPATH_LEAKAGE) {
+//            if (inProcess != JAVA_EXEC) {
+//                logger.warn 'EPUB processing on this version of Gradle will fail due to classpath issues. ' +
+//                    'Switching to JAVA_EXEC instead.'
+//            }
+//            return JAVA_EXEC
+//        }
+//        super.finalProcessMode
+//    }
 
     @CompileDynamic
     private Version getVersion(Matcher matcher) {
diff --git a/jvm-epub/src/main/groovy/org/asciidoctor/gradle/jvm/epub/AsciidoctorJEpubPlugin.groovy b/jvm-epub/src/main/groovy/org/asciidoctor/gradle/jvm/epub/AsciidoctorJEpubPlugin.groovy
index b47a8e7a5..34b2b50a5 100644
--- a/jvm-epub/src/main/groovy/org/asciidoctor/gradle/jvm/epub/AsciidoctorJEpubPlugin.groovy
+++ b/jvm-epub/src/main/groovy/org/asciidoctor/gradle/jvm/epub/AsciidoctorJEpubPlugin.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,11 +21,11 @@ import org.asciidoctor.gradle.jvm.AsciidoctorJExtension
 import org.gradle.api.Action
 import org.gradle.api.Plugin
 import org.gradle.api.Project
-import org.ysb33r.grolifant.api.v4.TaskProvider
 
 import static org.asciidoctor.gradle.base.AsciidoctorUtils.setConvention
 
-/** Provides additional conventions for building EPUBs.
+/**
+ * Provides additional conventions for building EPUBs.
  *
  * <ul>
  *   <li>Creates a task called {@code asciidoctorEpub}.
@@ -41,23 +41,21 @@ import static org.asciidoctor.gradle.base.AsciidoctorUtils.setConvention
 class AsciidoctorJEpubPlugin implements Plugin<Project> {
 
     void apply(Project project) {
-        project.with {
-            apply plugin: AsciidoctorJBasePlugin
-            extensions.getByType(AsciidoctorJExtension).modules.epub.use()
+        project.pluginManager.apply(AsciidoctorJBasePlugin)
+        project.extensions.getByType(AsciidoctorJExtension).modules.epub.use()
 
-            Action epubDefaults = new Action<AsciidoctorEpubTask>() {
-                @Override
-                void execute(AsciidoctorEpubTask task) {
-                    task.group = AsciidoctorJBasePlugin.TASK_GROUP
-                    task.description = 'Convert AsciiDoc files to EPUB3 formats'
-                    setConvention(project, task.sourceDirProperty,
+        Action epubDefaults = new Action<AsciidoctorEpubTask>() {
+            @Override
+            void execute(AsciidoctorEpubTask task) {
+                task.group = AsciidoctorJBasePlugin.TASK_GROUP
+                task.description = 'Convert AsciiDoc files to EPUB3 formats'
+                setConvention(project, task.sourceDirProperty,
                         project.layout.projectDirectory.dir('src/docs/asciidoc'))
-                    setConvention(task.outputDirProperty,
+                setConvention(task.outputDirProperty,
                         task.project.layout.buildDirectory.dir('docs/asciidocEpub'))
-                }
             }
-
-            TaskProvider.registerTask(project, 'asciidoctorEpub', AsciidoctorEpubTask, epubDefaults)
         }
+
+        project.tasks.register('asciidoctorEpub', AsciidoctorEpubTask, epubDefaults)
     }
 }
diff --git a/jvm-epub/src/main/resources/META-INF/gradle-plugins/org.asciidoctor.jvm.epub.properties b/jvm-epub/src/main/resources/META-INF/gradle-plugins/org.asciidoctor.jvm.epub.properties
deleted file mode 100644
index 278786f73..000000000
--- a/jvm-epub/src/main/resources/META-INF/gradle-plugins/org.asciidoctor.jvm.epub.properties
+++ /dev/null
@@ -1,17 +0,0 @@
-#
-# Copyright 2013-2023 the original author or 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
-#
-#     http://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.
-#
-
-implementation-class=org.asciidoctor.gradle.jvm.epub.AsciidoctorJEpubPlugin
\ No newline at end of file
diff --git a/jvm-leanpub/build.gradle b/jvm-leanpub/build.gradle
index 7b723a1f9..e5da5f53d 100644
--- a/jvm-leanpub/build.gradle
+++ b/jvm-leanpub/build.gradle
@@ -1,23 +1,24 @@
-dependencies {
-    compile project(':asciidoctor-gradle-jvm')
+agProject {
+    withOfflineTestConfigurations()
 
-    intTestOfflineRepo "org.asciidoctor:asciidoctorj:${compileOnlyAsciidoctorJVersion}"
-    intTestOfflineRepo "org.asciidoctor:asciidoctor-leanpub-markdown:${downloadOnlyLeanpubVersion}"
-}
+    configurePlugin 'org.asciidoctor.jvm.leanpub',
+            'AsciidoctorJ Leanpub Plugin',
+            'Asciidoctor task for creating content suitable for Leanpub',
+            'org.asciidoctor.gradle.jvm.leanpub.AsciidoctorJLeanpubPlugin',
+            ['asciidoctorj', 'leanpub', 'markdown', 'markuva']
+
+    configurePlugin 'org.asciidoctor.jvm.leanpub.dropbox-copy',
+            'Dropbox support for AsciidoctorJ Leanpub Plugin',
+            'Provides local Dropbox support for Asciidoctor Leanpub plugin',
+            'org.asciidoctor.gradle.jvm.leanpub.AsciidoctorJLeanpubDropboxCopyPlugin',
+            ['asciidoctorj', 'leanpub', 'markdown', 'markuva', 'dropbox']
 
-intTest {
-    systemProperties TEST_PROJECTS_DIR: file('src/intTest/projects')
 }
 
-configurePlugin 'org.asciidoctor.jvm.leanpub',
-    'AsciidoctorJ Leanpub Plugin',
-    'Asciidoctor task for creating content suitable for Leanpub',
-    ['asciidoctorj', 'leanpub', 'markdown', 'markuva']
+dependencies {
+    implementation project(':asciidoctor-gradle-jvm')
 
-configurePlugin 'org.asciidoctor.jvm.leanpub.dropbox-copy',
-    'Dropbox support for AsciidoctorJ Leanpub Plugin',
-    'Provides local Dropbox support for Asciidoctor Leanpub plugin',
-    ['asciidoctorj', 'leanpub', 'markdown', 'markuva', 'dropbox']
+    intTestOfflineRepo "org.asciidoctor:asciidoctorj:${compileOnlyAsciidoctorJVersion}"
+    intTestOfflineRepo "org.asciidoctor:asciidoctor-leanpub-markdown:${downloadOnlyLeanpubVersion}"
+}
 
-// TODO: Re-enable this after leanpub artifact appears on MavenCentral
-gradleTest.enabled = false
\ No newline at end of file
diff --git a/jvm-leanpub/src/intTest/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorLeanpubTaskFunctionalSpec.groovy b/jvm-leanpub/src/intTest/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorLeanpubTaskFunctionalSpec.groovy
index 32c8b579c..77e393450 100644
--- a/jvm-leanpub/src/intTest/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorLeanpubTaskFunctionalSpec.groovy
+++ b/jvm-leanpub/src/intTest/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorLeanpubTaskFunctionalSpec.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -36,49 +36,22 @@ class AsciidoctorLeanpubTaskFunctionalSpec extends FunctionalSpecification {
 
         then:
         verifyAll {
-            new File(testProjectDir.root, 'build/docs/asciidocLeanpub/manuscript/Book.txt').exists()
+            new File(projectDir, 'build/docs/asciidocLeanpub/manuscript/Book.txt').exists()
         }
 
         where:
         processMode << ProcessGenerator.get()
     }
 
-//    File getSingleFormatBuildFile(final String format) {
-//        getBuildFile( """
-//
-//        asciidoctorEpub {
-//            sourceDir 'src/docs/asciidoc'
-//            ebookFormats ${format}
-//
-//            kindlegen {
-//                agreeToTermsOfUse = true
-//            }
-//
-//            asciidoctorj {
-//                jrubyVersion = '${JRUBY_TEST_VERSION}'
-//            }
-//
-//            sources {
-//                include 'epub3.adoc'
-//            }
-//        }
-//        """)
-//    }
-
     File getBuildFile(String extraContent, boolean withDropbox = false) {
-        File buildFile = testProjectDir.newFile('build.gradle')
-        buildFile << """
-plugins {
-    id 'org.asciidoctor.jvm.leanpub'
-
-    ${withDropbox ? "id 'org.asciidoctor.jvm.leanpub.dropbox-copy'" : ''}
-}
-
-${offlineRepositories}
-
-${extraContent}
-"""
-        buildFile
+        if (withDropbox) {
+            writeGroovyBuildFile(
+                    ['org.asciidoctor.jvm.leanpub', 'org.asciidoctor.jvm.leanpub.dropbox-copy'],
+                    extraContent
+            )
+        } else {
+            getJvmConvertGroovyBuildFile(extraContent)
+        }
     }
 
 }
\ No newline at end of file
diff --git a/jvm-leanpub/src/intTest/groovy/org/asciidoctor/gradle/jvm/leanpub/internal/FunctionalSpecification.groovy b/jvm-leanpub/src/intTest/groovy/org/asciidoctor/gradle/jvm/leanpub/internal/FunctionalSpecification.groovy
index f13d3aacf..68b0b7424 100644
--- a/jvm-leanpub/src/intTest/groovy/org/asciidoctor/gradle/jvm/leanpub/internal/FunctionalSpecification.groovy
+++ b/jvm-leanpub/src/intTest/groovy/org/asciidoctor/gradle/jvm/leanpub/internal/FunctionalSpecification.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,72 +17,44 @@ package org.asciidoctor.gradle.jvm.leanpub.internal
 
 import groovy.transform.CompileStatic
 import org.apache.commons.io.FileUtils
-import org.asciidoctor.gradle.testfixtures.DslType
+import org.asciidoctor.gradle.testfixtures.FunctionalTestFixture
 import org.asciidoctor.gradle.testfixtures.FunctionalTestSetup
 import org.gradle.testkit.runner.GradleRunner
-import org.junit.Rule
-import org.junit.rules.TemporaryFolder
-import org.ysb33r.grolifant.api.core.OperatingSystem
 import spock.lang.Specification
+import spock.lang.TempDir
 
 import static org.asciidoctor.gradle.testfixtures.DslType.GROOVY_DSL
-import static org.asciidoctor.gradle.testfixtures.DslType.KOTLIN_DSL
-import static org.asciidoctor.gradle.testfixtures.FunctionalTestSetup.getOfflineRepositoriesGroovyDsl
-import static org.asciidoctor.gradle.testfixtures.FunctionalTestSetup.getOfflineRepositoriesKotlinDsl
 
-class FunctionalSpecification extends Specification {
+class FunctionalSpecification extends Specification implements FunctionalTestFixture {
     public static final String TEST_PROJECTS_DIR = System.getProperty(
-        'TEST_PROJECTS_DIR',
-        './src/intTest/projects'
+            'TEST_PROJECTS_DIR',
+            './src/intTest/projects'
     )
     public static final String TEST_REPO_DIR = FunctionalTestSetup.offlineRepo.absolutePath
-//    public static final OperatingSystem OS = OperatingSystem.current()
 
-    @Rule
-    TemporaryFolder testProjectDir = new TemporaryFolder()
+    @TempDir
+    File testProjectDir
+
+    void setup() {
+        projectDir.mkdirs()
+    }
 
     @CompileStatic
     GradleRunner getGradleRunner(List<String> taskNames = ['asciidoctor']) {
-        FunctionalTestSetup.getGradleRunner(GROOVY_DSL, testProjectDir.root, taskNames)
+        FunctionalTestSetup.getGradleRunner(GROOVY_DSL, projectDir, taskNames)
     }
 
     @SuppressWarnings(['BuilderMethodWithSideEffects'])
     void createTestProject(String docGroup = 'leanpub') {
-        FileUtils.copyDirectory(new File(TEST_PROJECTS_DIR, docGroup), testProjectDir.root)
+        FileUtils.copyDirectory(new File(TEST_PROJECTS_DIR, docGroup), projectDir)
     }
 
-    @CompileStatic
-    String getOfflineRepositories(DslType dslType = GROOVY_DSL) {
-        dslType == GROOVY_DSL ? getOfflineRepositoriesGroovyDsl(new File(TEST_REPO_DIR)) :
-            getOfflineRepositoriesKotlinDsl(new File(TEST_REPO_DIR))
+    File getJvmConvertGroovyBuildFile(String extraContent) {
+        writeGroovyBuildFile('org.asciidoctor.jvm.leanpub', extraContent)
     }
 
-    File getJvmConvertGroovyBuildFile(String extraContent, String plugin = 'org.asciidoctor.jvm.leanpub') {
-        File buildFile = testProjectDir.newFile('build.gradle')
-        buildFile << """
-            plugins {
-                id '${plugin}'
-            }
-
-            ${offlineRepositories}
-
-            ${extraContent}
-        """
-        buildFile
-    }
-
-    File getJvmConvertKotlinBuildFile(String extraContent, String plugin = 'org.asciidoctor.jvm.leanpub') {
-        File buildFile = testProjectDir.newFile('build.gradle.kts')
-        buildFile << """
-            plugins {
-                id ("${plugin}")
-            }
-
-            ${getOfflineRepositories(KOTLIN_DSL)}
-
-            ${extraContent}
-        """
-        buildFile
+    File getJvmConvertKotlinBuildFile(String extraContent) {
+        writeKotlinBuildFile('org.asciidoctor.jvm.leanpub', extraContent)
     }
 
 }
\ No newline at end of file
diff --git a/jvm-leanpub/src/main/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorJLeanpubDropboxCopyPlugin.groovy b/jvm-leanpub/src/main/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorJLeanpubDropboxCopyPlugin.groovy
index 9df4298e2..9be6aa331 100644
--- a/jvm-leanpub/src/main/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorJLeanpubDropboxCopyPlugin.groovy
+++ b/jvm-leanpub/src/main/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorJLeanpubDropboxCopyPlugin.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,11 +16,8 @@
 package org.asciidoctor.gradle.jvm.leanpub
 
 import groovy.transform.CompileStatic
-import org.gradle.api.Action
 import org.gradle.api.Plugin
 import org.gradle.api.Project
-import org.gradle.api.Task
-import org.ysb33r.grolifant.api.v4.TaskProvider
 
 /** Adds a task to copy Leanpub task output to a Dropbox folder.
  *
@@ -30,28 +27,20 @@ import org.ysb33r.grolifant.api.v4.TaskProvider
  */
 @CompileStatic
 class AsciidoctorJLeanpubDropboxCopyPlugin implements Plugin<Project> {
-
     public final static String LEANPUB_TASK_NAME = AsciidoctorJLeanpubPlugin.TASK_NAME
     public final static String COPY_TASK_NAME = "copy${LEANPUB_TASK_NAME.capitalize()}ToDropbox"
 
     @Override
     void apply(Project project) {
-        project.apply plugin: AsciidoctorJLeanpubPlugin
-        Action copyConfig = new Action<DropboxCopyTask>() {
-            @Override
-            void execute(DropboxCopyTask dropboxCopyTask) {
-                dropboxCopyTask.with {
-                    dependsOn(LEANPUB_TASK_NAME)
-                    sourceDir = {
-                        Task task = project.tasks.getByName(LEANPUB_TASK_NAME.toString())
-                        new File(
-                            ((AsciidoctorLeanpubTask) task).outputDir,
-                            'manuscript'
-                        )
-                    }
-                }
-            }
+        project.pluginManager.apply(AsciidoctorJLeanpubPlugin)
+        final leanpubTask = project.tasks.named(LEANPUB_TASK_NAME, AsciidoctorLeanpubTask)
+        final leanpubSourceDir = leanpubTask.map {
+            new File(it.outputDir, 'manuscript')
+        }
+
+        project.tasks.register(COPY_TASK_NAME, DropboxCopyTask) { t ->
+            t.dependsOn(leanpubTask)
+            t.sourceDir = leanpubSourceDir
         }
-        TaskProvider.registerTask(project, COPY_TASK_NAME, DropboxCopyTask, copyConfig)
     }
 }
diff --git a/jvm-leanpub/src/main/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorJLeanpubPlugin.groovy b/jvm-leanpub/src/main/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorJLeanpubPlugin.groovy
index c08203805..a1bedad98 100644
--- a/jvm-leanpub/src/main/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorJLeanpubPlugin.groovy
+++ b/jvm-leanpub/src/main/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorJLeanpubPlugin.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,7 +21,6 @@ import org.asciidoctor.gradle.jvm.AsciidoctorJExtension
 import org.gradle.api.Action
 import org.gradle.api.Plugin
 import org.gradle.api.Project
-import org.ysb33r.grolifant.api.v4.TaskProvider
 
 import static org.asciidoctor.gradle.base.AsciidoctorUtils.setConvention
 
@@ -43,23 +42,22 @@ class AsciidoctorJLeanpubPlugin implements Plugin<Project> {
     public final static String TASK_NAME = 'asciidoctorLeanpub'
 
     void apply(Project project) {
-        project.with {
-            apply plugin: AsciidoctorJBasePlugin
+        project.pluginManager.apply(AsciidoctorJBasePlugin)
 
-            Action leanpubDefaults = new Action<AsciidoctorLeanpubTask>() {
-                @Override
-                void execute(AsciidoctorLeanpubTask task) {
-                    task.group = AsciidoctorJBasePlugin.TASK_GROUP
-                    task.description = 'Convert AsciiDoc files to Leanpub-structured Markdown'
-                    setConvention(task.project, task.sourceDirProperty,
-                            project.layout.projectDirectory.dir('src/docs/asciidoc'))
-                    setConvention(task.outputDirProperty,
-                            task.project.layout.buildDirectory.dir('docs/asciidocLeanpub'))
-                }
+        Action leanpubDefaults = new Action<AsciidoctorLeanpubTask>() {
+            @Override
+            void execute(AsciidoctorLeanpubTask task) {
+                task.group = AsciidoctorJBasePlugin.TASK_GROUP
+                task.description = 'Convert AsciiDoc files to Leanpub-structured Markdown'
+                setConvention(task.project, task.sourceDirProperty,
+                        project.layout.projectDirectory.dir('src/docs/asciidoc'))
+                setConvention(task.outputDirProperty,
+                        task.project.layout.buildDirectory.dir('docs/asciidocLeanpub'))
             }
-
-            TaskProvider.registerTask(project, TASK_NAME, AsciidoctorLeanpubTask, leanpubDefaults)
-            extensions.getByType(AsciidoctorJExtension).modules.leanpub.use()
         }
+
+        project.tasks.register(TASK_NAME, AsciidoctorLeanpubTask, leanpubDefaults)
+        project.extensions.getByType(AsciidoctorJExtension).modules.leanpub.use()
     }
 }
+
diff --git a/jvm-leanpub/src/main/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorLeanpubTask.groovy b/jvm-leanpub/src/main/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorLeanpubTask.groovy
index 7b7f7f820..5953cbd77 100644
--- a/jvm-leanpub/src/main/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorLeanpubTask.groovy
+++ b/jvm-leanpub/src/main/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorLeanpubTask.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -47,12 +47,13 @@ class AsciidoctorLeanpubTask extends AbstractAsciidoctorTask {
     AsciidoctorLeanpubTask(WorkerExecutor we) {
         super(we)
 
-        configuredOutputOptions.backends = [BACKEND]
+        outputOptions.backends = [BACKEND]
         copyNoResources()
         asciidoctorj.options.put('doctype', 'book')
     }
 
-    /** The style used to format colists.
+    /**
+     * The style used to format colists.
      *
      * @return Colist style
      */
@@ -74,7 +75,8 @@ class AsciidoctorLeanpubTask extends AbstractAsciidoctorTask {
         this.colistPrefix = val
     }
 
-    /** A task may add some default attributes.
+    /**
+     * A task may add some default attributes.
      *
      * If the user specifies any of the attributes, then these attributes will not be utilised.
      *
@@ -85,11 +87,13 @@ class AsciidoctorLeanpubTask extends AbstractAsciidoctorTask {
      * @return A collection of default attributes.
      */
     @Override
-    protected Map<String, Object> getTaskSpecificDefaultAttributes(File workingSourceDir) {
-        Map<String,Object> attrs = super.getTaskSpecificDefaultAttributes(workingSourceDir)
-//        attrs.put 'front-cover-image', getFrontCoverImage()
-        attrs.put 'leanpub-colist-style', getColistStyle()
-        attrs.put 'leanpub-colist-prefix', getColistPrefix()
+    Map<String, ?> getTaskSpecificDefaultAttributes(File workingSourceDir) {
+        Map<String, ?> attrs = super.getTaskSpecificDefaultAttributes(workingSourceDir)
+        attrs.putAll([
+                //                'front-cover-image': getFrontCoverImage(),
+                'leanpub-colist-style' : colistStyle,
+                'leanpub-colist-prefix': colistPrefix
+        ])
         attrs
     }
 }
diff --git a/jvm-leanpub/src/main/groovy/org/asciidoctor/gradle/jvm/leanpub/DropboxCopyTask.groovy b/jvm-leanpub/src/main/groovy/org/asciidoctor/gradle/jvm/leanpub/DropboxCopyTask.groovy
index 688da5b3e..45cfdf365 100644
--- a/jvm-leanpub/src/main/groovy/org/asciidoctor/gradle/jvm/leanpub/DropboxCopyTask.groovy
+++ b/jvm-leanpub/src/main/groovy/org/asciidoctor/gradle/jvm/leanpub/DropboxCopyTask.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -26,9 +26,10 @@ import org.gradle.api.tasks.OutputDirectory
 import org.gradle.api.tasks.PathSensitive
 import org.gradle.api.tasks.PathSensitivity
 import org.gradle.api.tasks.TaskAction
-import org.ysb33r.grolifant.api.v4.StringUtils
+import org.ysb33r.grolifant.api.core.ProjectOperations
 
-/** Copies Leanpub Asciidoctor task output to a Dropbox folder.
+/**
+ * Copies Leanpub Asciidoctor task output to a Dropbox folder.
  *
  * @author Schalk W. Cronjé
  *
@@ -37,6 +38,7 @@ import org.ysb33r.grolifant.api.v4.StringUtils
 @CompileStatic
 class DropboxCopyTask extends DefaultTask {
 
+    private final ProjectOperations projectOperations
     private Object dropboxRoot = "${System.getProperty('user.home')}/Dropbox"
     private Object bookPath
     private Object sourceDir
@@ -50,13 +52,17 @@ class DropboxCopyTask extends DefaultTask {
         }
     }
 
+    DropboxCopyTask() {
+        this.projectOperations = ProjectOperations.find(project)
+    }
+
     /** Root directory on filesystem where Dropbox synchronises all files.
      *
      * @return Path to Dropbox root on local filesystem.
      */
     @Internal
     File getDropboxRoot() {
-        project.file(this.dropboxRoot)
+        projectOperations.fsOperations.file(this.dropboxRoot)
     }
 
     /** Override location of Dropbox root
@@ -75,7 +81,7 @@ class DropboxCopyTask extends DefaultTask {
      */
     @Input
     String getBookPath() {
-        this.bookPath != null ? StringUtils.stringize(this.bookPath) : null
+        this.bookPath != null ? projectOperations.stringTools.stringize(this.bookPath) : null
     }
 
     /** Sets the relative path of the Leanpub book in Dropbox.
@@ -95,7 +101,7 @@ class DropboxCopyTask extends DefaultTask {
     @InputDirectory
     @PathSensitive(PathSensitivity.RELATIVE)
     File getSourceDir() {
-        project.file(this.sourceDir)
+        projectOperations.fsOperations.file(this.sourceDir)
     }
 
     void setSourceDir(Object s) {
@@ -108,11 +114,11 @@ class DropboxCopyTask extends DefaultTask {
      */
     @OutputDirectory
     File getDestinationDir() {
-        project.file("${getDropboxRoot()}/${getBookPath()}/manuscript")
+        projectOperations.fsOperations.file("${getDropboxRoot()}/${getBookPath()}/manuscript")
     }
 
     @TaskAction
     void copy() {
-        project.copy(copySpec)
+        projectOperations.copy(copySpec)
     }
 }
diff --git a/jvm-leanpub/src/main/resources/META-INF/gradle-plugins/org.asciidoctor.jvm.leanpub.dropbox-copy.properties b/jvm-leanpub/src/main/resources/META-INF/gradle-plugins/org.asciidoctor.jvm.leanpub.dropbox-copy.properties
deleted file mode 100644
index 7262db0de..000000000
--- a/jvm-leanpub/src/main/resources/META-INF/gradle-plugins/org.asciidoctor.jvm.leanpub.dropbox-copy.properties
+++ /dev/null
@@ -1,17 +0,0 @@
-#
-# Copyright 2013-2023 the original author or 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
-#
-#     http://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.
-#
-
-implementation-class=org.asciidoctor.gradle.jvm.leanpub.AsciidoctorJLeanpubDropboxCopyPlugin
\ No newline at end of file
diff --git a/jvm-leanpub/src/main/resources/META-INF/gradle-plugins/org.asciidoctor.jvm.leanpub.properties b/jvm-leanpub/src/main/resources/META-INF/gradle-plugins/org.asciidoctor.jvm.leanpub.properties
deleted file mode 100644
index aa3f3cf02..000000000
--- a/jvm-leanpub/src/main/resources/META-INF/gradle-plugins/org.asciidoctor.jvm.leanpub.properties
+++ /dev/null
@@ -1,17 +0,0 @@
-#
-# Copyright 2013-2023 the original author or 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
-#
-#     http://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.
-#
-
-implementation-class=org.asciidoctor.gradle.jvm.leanpub.AsciidoctorJLeanpubPlugin
\ No newline at end of file
diff --git a/jvm-leanpub/src/test/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorJLeanpubPluginSpec.groovy b/jvm-leanpub/src/test/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorJLeanpubPluginSpec.groovy
index 709f0b18e..31c53e54b 100644
--- a/jvm-leanpub/src/test/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorJLeanpubPluginSpec.groovy
+++ b/jvm-leanpub/src/test/groovy/org/asciidoctor/gradle/jvm/leanpub/AsciidoctorJLeanpubPluginSpec.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/jvm-leanpub/src/test/groovy/org/asciidoctor/gradle/jvm/leanpub/DropboxCopyTaskSpec.groovy b/jvm-leanpub/src/test/groovy/org/asciidoctor/gradle/jvm/leanpub/DropboxCopyTaskSpec.groovy
index 730993ced..fba6170bd 100644
--- a/jvm-leanpub/src/test/groovy/org/asciidoctor/gradle/jvm/leanpub/DropboxCopyTaskSpec.groovy
+++ b/jvm-leanpub/src/test/groovy/org/asciidoctor/gradle/jvm/leanpub/DropboxCopyTaskSpec.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/jvm-pdf/build.gradle b/jvm-pdf/build.gradle
index 0daf68860..4cef309e6 100644
--- a/jvm-pdf/build.gradle
+++ b/jvm-pdf/build.gradle
@@ -1,32 +1,28 @@
-
-agpProject {
+agProject {
     withOfflineTestConfigurations()
+
+    configurePlugin(
+            'org.asciidoctor.jvm.pdf',
+            'AsciidoctorJ PDF Conversion Plugin',
+            'Simplifies conversion of asciidoc documents to PDF',
+            'org.asciidoctor.gradle.jvm.pdf.AsciidoctorJPdfPlugin',
+            ['asciidoctorj', 'pdf']
+    )
 }
+
 dependencies {
     implementation project(':asciidoctor-gradle-jvm')
     intTestOfflineRepo "org.asciidoctor:asciidoctorj:${compileOnlyAsciidoctorJVersion}"
     intTestOfflineRepo "org.asciidoctor:asciidoctorj-pdf:${downloadOnlyPdfVersion}"
 }
 
-test {
+tasks.named('test', Test) {
     systemProperties TEST_THEMES_DIR: file('src/test/resources/themes')
 }
 
-intTest {
-    systemProperties TEST_PROJECTS_DIR: file('src/intTest/projects')
+tasks.named('intTest', Test) {
+    maxParallelForks = 2
+    forkEvery = 1
+    maxHeapSize = '2048m'
 }
 
-gradlePlugin {
-    plugins {
-        convertPlugin {
-            id = 'org.asciidoctor.jvm.pdf'
-            displayName = 'AsciidoctorJ PDF Conversion Plugin'
-            description = "Simplifies conversion of asciidoc documents to PDF${pluginExtraText}"
-//            tags.set(['asciidoctorj', 'pdf'])
-            implementationClass = 'org.asciidoctor.gradle.jvm.pdf.AsciidoctorJPdfPlugin'
-        }
-    }
-}
-
-
-//gradleTest.gradleArguments '-s'
\ No newline at end of file
diff --git a/jvm-pdf/src/gradleTest/complex-jvm-setup/build.gradle b/jvm-pdf/src/gradleTest/complex-jvm-setup/build.gradle
index 0d61ef1f5..f09ad7438 100644
--- a/jvm-pdf/src/gradleTest/complex-jvm-setup/build.gradle
+++ b/jvm-pdf/src/gradleTest/complex-jvm-setup/build.gradle
@@ -15,7 +15,7 @@ asciidoctorj {
 }
 
 asciidoctorPdf {
-    inProcess OUT_OF_PROCESS
+    executionMode = OUT_OF_PROCESS
     logDocuments true
     sourceDir 'src/docs/asciidoc'
 
diff --git a/jvm-pdf/src/gradleTest/complex-jvm-setup/build.gradle.kts b/jvm-pdf/src/gradleTest/complex-jvm-setup/build.gradle.kts
index 4151fcfb1..d154c6d64 100644
--- a/jvm-pdf/src/gradleTest/complex-jvm-setup/build.gradle.kts
+++ b/jvm-pdf/src/gradleTest/complex-jvm-setup/build.gradle.kts
@@ -4,11 +4,10 @@ import org.asciidoctor.gradle.base.process.ProcessMode
 // tag::using-two-plugins-three-backends[]
 plugins {
     id("org.asciidoctor.jvm.pdf")
-//    id("com.gradle.build-scan") version "1.16"
 }
 
 repositories {
-    jcenter()
+    mavenCentral()
 }
 
 asciidoctorj {
@@ -17,7 +16,7 @@ asciidoctorj {
 }
 
 tasks.named<AsciidoctorPdfTask>("asciidoctorPdf") {
-    inProcess = ProcessMode.OUT_OF_PROCESS
+    setExecutionMode("OUT_OF_PROCESS")
     logDocuments = true
     setSourceDir("src/docs/asciidoc")
 
diff --git a/jvm-pdf/src/intTest/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfTaskCachingFunctionalSpec.groovy b/jvm-pdf/src/intTest/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfTaskCachingFunctionalSpec.groovy
index 634450f78..7b4bf03f5 100644
--- a/jvm-pdf/src/intTest/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfTaskCachingFunctionalSpec.groovy
+++ b/jvm-pdf/src/intTest/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfTaskCachingFunctionalSpec.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,14 +16,16 @@
 package org.asciidoctor.gradle.jvm.pdf
 
 import org.asciidoctor.gradle.jvm.pdf.internal.FunctionalSpecification
-import org.asciidoctor.gradle.testfixtures.CachingTest
+import org.asciidoctor.gradle.testfixtures.BuildScanFixture
+import org.asciidoctor.gradle.testfixtures.CachingTestFixture
 import spock.lang.PendingFeature
 
 /** AsciidoctorPdfTaskCachingFunctionalSpec
  *
  * @author Gary Hale
  */
-class AsciidoctorPdfTaskCachingFunctionalSpec extends FunctionalSpecification implements CachingTest {
+class AsciidoctorPdfTaskCachingFunctionalSpec extends FunctionalSpecification
+        implements CachingTestFixture, BuildScanFixture {
     static final String DEFAULT_TASK = 'asciidoctorPdf'
     static final String DEFAULT_OUTPUT_FILE = 'build/docs/asciidocPdf/sample.pdf'
 
@@ -54,7 +56,8 @@ class AsciidoctorPdfTaskCachingFunctionalSpec extends FunctionalSpecification im
         outputFileInRelocatedDirectory.exists()
     }
 
-    @PendingFeature // TODO: Come back and fix caching
+    @PendingFeature
+    // TODO: Come back and fix caching
     void "PDF task is not cached when pdf-specific inputs change"() {
         given:
         getBuildFile("""
@@ -80,8 +83,8 @@ class AsciidoctorPdfTaskCachingFunctionalSpec extends FunctionalSpecification im
         when:
         file('src/docs/themes/pdf-theme').mkdirs()
         file('src/docs/themes/pdf-theme/basic-theme.yml').text =
-            file('src/docs/asciidoc/pdf-theme/basic-theme.yml').text
-                .replace('333333', '333334')
+                file('src/docs/asciidoc/pdf-theme/basic-theme.yml').text
+                        .replace('333333', '333334')
 
         changeBuildConfigurationTo("""
             pdfThemes {
@@ -109,18 +112,9 @@ class AsciidoctorPdfTaskCachingFunctionalSpec extends FunctionalSpecification im
     }
 
     File getBuildFile(String extraContent) {
-        File buildFile = testProjectDir.newFile('build.gradle')
-        buildFile << """
-            plugins {
-                id 'org.asciidoctor.jvm.pdf'
-            }
-            
-            ${ -> scan ? buildScanConfiguration : '' }
-            ${offlineRepositories}
-            
-            ${extraContent}
-        """
-        buildFile
+        writeGroovyBuildFile('org.asciidoctor.jvm.pdf', extraContent).withWriterAppend { w ->
+            w.println(performBuildScan ? buildScanConfiguration : '')
+        }
     }
 
     String getDefaultTask() {
diff --git a/jvm-pdf/src/intTest/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfTaskFunctionalSpec.groovy b/jvm-pdf/src/intTest/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfTaskFunctionalSpec.groovy
index f9767a95c..1d7b29678 100644
--- a/jvm-pdf/src/intTest/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfTaskFunctionalSpec.groovy
+++ b/jvm-pdf/src/intTest/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfTaskFunctionalSpec.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -55,7 +55,7 @@ asciidoctorPdf {
 
         then:
         verifyAll {
-            new File(testProjectDir.root, DEFAULT_OUTPUT_FILE).exists()
+            new File(projectDir, DEFAULT_OUTPUT_FILE).exists()
         }
 
         where:
@@ -91,7 +91,7 @@ asciidoctorPdf {
         combination.compatible ? runner.build() : runner.buildAndFail()
 
         then:
-        combination.compatible && new File(testProjectDir.root, DEFAULT_OUTPUT_FILE).exists() || !combination.compatible
+        combination.compatible && new File(projectDir, DEFAULT_OUTPUT_FILE).exists() || !combination.compatible
 
         where:
         combination << PdfBackendJRubyAsciidoctorJCombinationGenerator.get()
@@ -103,7 +103,7 @@ asciidoctorPdf {
         asciidoctorPdf {
             sourceDir 'src/docs/asciidoc'
 
-            inProcess = JAVA_EXEC
+            executionMode = JAVA_EXEC
         }
         """)
 
@@ -112,7 +112,7 @@ asciidoctorPdf {
 
         then:
         verifyAll {
-            new File(testProjectDir.root, DEFAULT_OUTPUT_FILE).exists()
+            new File(projectDir, DEFAULT_OUTPUT_FILE).exists()
         }
     }
 
@@ -137,7 +137,7 @@ asciidoctorPdf {
 
         then:
         verifyAll {
-            new File(testProjectDir.root, DEFAULT_OUTPUT_FILE).exists()
+            new File(projectDir, DEFAULT_OUTPUT_FILE).exists()
         }
     }
 
@@ -156,6 +156,7 @@ asciidoctorPdf {
             sourceDir 'src/docs/asciidoc'
             fontsDirs 'src/docs/asciidoc/pdf-theme', file('src/docs/asciidoc/path')
             fontsDirs 'src/docs/asciidoc/pdf-theme-path'
+            executionMode = JAVA_EXEC
         }
         """)
 
@@ -164,7 +165,7 @@ asciidoctorPdf {
 
         then:
         verifyAll {
-            new File(testProjectDir.root, DEFAULT_OUTPUT_FILE).exists()
+            new File(projectDir, DEFAULT_OUTPUT_FILE).exists()
         }
     }
 
@@ -182,15 +183,16 @@ asciidoctorPdf {
             theme 'basic'
             sourceDir 'src/docs/asciidoc'
             fontsDirs 'src/docs/asciidoc/pdf-theme'
+            executionMode = JAVA_EXEC
         }
-        """)
+        """.stripIndent())
 
         when:
         getGradleRunner([DEFAULT_TASK, '-i']).build()
 
         then:
         verifyAll {
-            new File(testProjectDir.root, DEFAULT_OUTPUT_FILE).exists()
+            new File(projectDir, DEFAULT_OUTPUT_FILE).exists()
         }
     }
 
@@ -198,22 +200,23 @@ asciidoctorPdf {
     @Unroll
     void 'can apply a task configuration rule to set source and output directory (Gradle #gradleVersion)'() {
         given:
-        File newSourceDir = new File(testProjectDir.root, 'src/asciidoc')
-        assert new File(testProjectDir.root, 'src/docs/asciidoc').renameTo(newSourceDir)
-        testProjectDir.newFile('build.gradle') << """
+        File newSourceDir = new File(projectDir, 'src/asciidoc')
+        assert new File(projectDir, 'src/docs/asciidoc').renameTo(newSourceDir)
+        buildFile.text = """
             plugins {
                 id 'org.asciidoctor.jvm.pdf' apply false
             }
 
-            tasks.withType(org.asciidoctor.gradle.jvm.pdf.AsciidoctorPdfTask) {
+            tasks.withType(org.asciidoctor.gradle.jvm.pdf.AsciidoctorPdfTask).configureEach {
                 sourceDir = 'src/asciidoc'
                 outputDir = "\${buildDir}/output"
+                executionMode = JAVA_EXEC
             }
 
             apply plugin: 'org.asciidoctor.jvm.pdf'
             
             ${offlineRepositories}
-        """
+        """.stripIndent()
 
         when:
         getGradleRunner([DEFAULT_TASK, '-s'])
@@ -222,11 +225,11 @@ asciidoctorPdf {
 
         then:
         verifyAll {
-            new File(testProjectDir.root, 'build/output/sample.pdf').exists()
+            new File(projectDir, 'build/output/sample.pdf').exists()
         }
 
         where:
-        gradleVersion << [latestMinimumOrThis('6.0.1'), latestMinimumOrThis('6.9.1'), GradleTestVersions.MAX_VERSION]
+        gradleVersion << [latestMinimumOrThis('7.0.1'), GradleTestVersions.MAX_VERSION]
     }
 
     @Issue('https://github.com/asciidoctor/asciidoctor-gradle-plugin/issues/579')
@@ -250,17 +253,7 @@ asciidoctorPdf {
     }
 
     File getBuildFile(String extraContent) {
-        File buildFile = testProjectDir.newFile('build.gradle')
-        buildFile << """
-plugins {
-    id 'org.asciidoctor.jvm.pdf'
-}
-
-${offlineRepositories}
-
-${extraContent}
-"""
-        buildFile
+        writeGroovyBuildFile('org.asciidoctor.jvm.pdf', extraContent)
     }
 
     String getResolutionStrategy(final String asciidoctorjVer, final String jrubyVer) {
diff --git a/jvm-pdf/src/intTest/groovy/org/asciidoctor/gradle/jvm/pdf/internal/FunctionalSpecification.groovy b/jvm-pdf/src/intTest/groovy/org/asciidoctor/gradle/jvm/pdf/internal/FunctionalSpecification.groovy
index 3b2a0384e..bcd4c0b81 100644
--- a/jvm-pdf/src/intTest/groovy/org/asciidoctor/gradle/jvm/pdf/internal/FunctionalSpecification.groovy
+++ b/jvm-pdf/src/intTest/groovy/org/asciidoctor/gradle/jvm/pdf/internal/FunctionalSpecification.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -18,18 +18,15 @@ package org.asciidoctor.gradle.jvm.pdf.internal
 import groovy.transform.CompileStatic
 import org.apache.commons.io.FileUtils
 import org.asciidoctor.gradle.testfixtures.DslType
+import org.asciidoctor.gradle.testfixtures.FunctionalTestFixture
 import org.asciidoctor.gradle.testfixtures.FunctionalTestSetup
 import org.gradle.testkit.runner.GradleRunner
-import org.junit.Rule
-import org.junit.rules.TemporaryFolder
 import spock.lang.Specification
+import spock.lang.TempDir
 
 import static org.asciidoctor.gradle.testfixtures.DslType.GROOVY_DSL
-import static org.asciidoctor.gradle.testfixtures.DslType.KOTLIN_DSL
-import static org.asciidoctor.gradle.testfixtures.FunctionalTestSetup.getOfflineRepositoriesGroovyDsl
-import static org.asciidoctor.gradle.testfixtures.FunctionalTestSetup.getOfflineRepositoriesKotlinDsl
 
-class FunctionalSpecification extends Specification {
+class FunctionalSpecification extends Specification implements FunctionalTestFixture {
 
     @SuppressWarnings('LineLength')
     static
@@ -37,54 +34,24 @@ class FunctionalSpecification extends Specification {
     static
     final String TEST_REPO_DIR = FunctionalTestSetup.offlineRepo.absolutePath
 
-    @Rule
-    TemporaryFolder testProjectDir
+    @TempDir
+    File testProjectDir
 
-    @Rule
-    TemporaryFolder alternateProjectDir
+    File testKitDir
+
+    void setup() {
+        testKitDir = new File(testProjectDir, ".testkit-${UUID.randomUUID()}")
+        projectDir.mkdirs()
+    }
 
     @CompileStatic
     GradleRunner getGradleRunner(List<String> taskNames = ['asciidoctor']) {
-        FunctionalTestSetup.getGradleRunner(GROOVY_DSL, testProjectDir.root, taskNames)
+        FunctionalTestSetup.getGradleRunner(GROOVY_DSL, projectDir, taskNames).withTestKitDir(testKitDir)
     }
 
     @SuppressWarnings(['BuilderMethodWithSideEffects'])
     void createTestProject(String docGroup = 'normal') {
-        FileUtils.copyDirectory(new File(TEST_PROJECTS_DIR, docGroup), testProjectDir.root)
-    }
-
-    @CompileStatic
-    String getOfflineRepositories(DslType dslType = GROOVY_DSL) {
-        dslType == GROOVY_DSL ? getOfflineRepositoriesGroovyDsl(new File(TEST_REPO_DIR)) :
-            getOfflineRepositoriesKotlinDsl(new File(TEST_REPO_DIR))
-    }
-
-    File getJvmConvertGroovyBuildFile(String extraContent, String plugin = 'org.asciidoctor.jvm.pdf') {
-        File buildFile = testProjectDir.newFile('build.gradle')
-        buildFile << """
-            plugins {
-                id '${plugin}'
-            }
-
-            ${offlineRepositories}
-
-            ${extraContent}
-        """
-        buildFile
-    }
-
-    File getJvmConvertKotlinBuildFile(String extraContent, String plugin = 'org.asciidoctor.jvm.pdf') {
-        File buildFile = testProjectDir.newFile('build.gradle.kts')
-        buildFile << """
-            plugins {
-                id ("${plugin}")
-            }
-
-            ${getOfflineRepositories(KOTLIN_DSL)}
-
-            ${extraContent}
-        """
-        buildFile
+        FileUtils.copyDirectory(new File(TEST_PROJECTS_DIR, docGroup), projectDir)
     }
 
     String getDefaultProcessModeForAppveyor(final DslType dslType = GROOVY_DSL) {
diff --git a/jvm-pdf/src/main/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorJPdfPlugin.groovy b/jvm-pdf/src/main/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorJPdfPlugin.groovy
index a22d8a661..9e835d4d6 100644
--- a/jvm-pdf/src/main/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorJPdfPlugin.groovy
+++ b/jvm-pdf/src/main/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorJPdfPlugin.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/jvm-pdf/src/main/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfTask.groovy b/jvm-pdf/src/main/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfTask.groovy
index 2fd9e17a3..0345b4766 100644
--- a/jvm-pdf/src/main/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfTask.groovy
+++ b/jvm-pdf/src/main/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfTask.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,19 +15,14 @@
  */
 package org.asciidoctor.gradle.jvm.pdf
 
-import groovy.transform.CompileDynamic
 import groovy.transform.CompileStatic
-import org.asciidoctor.gradle.base.process.ProcessMode
 import org.asciidoctor.gradle.jvm.AbstractAsciidoctorTask
-import org.asciidoctor.gradle.jvm.AsciidoctorJExtension
 import org.gradle.api.Project
 import org.gradle.api.UnknownDomainObjectException
 import org.gradle.api.file.FileCollection
-import org.gradle.api.model.ReplacedBy
 @java.lang.SuppressWarnings('NoWildcardImports')
 import org.gradle.api.tasks.*
 import org.gradle.api.tasks.util.PatternSet
-import org.gradle.util.GradleVersion
 import org.gradle.workers.WorkerExecutor
 
 import javax.inject.Inject
@@ -48,61 +43,29 @@ import static org.ysb33r.grolifant.api.core.TaskInputFileOptions.OPTIONAL
 class AsciidoctorPdfTask extends AbstractAsciidoctorTask {
 
     private String theme
-    private final List<Object> fontDirs = []
+    private final List<Object> pdfFontDirs = []
 
     @Inject
     AsciidoctorPdfTask(WorkerExecutor we) {
         super(we)
 
-        configuredOutputOptions.backends = ['pdf']
+        outputOptions.backends = ['pdf']
         copyNoResources()
         projectOperations.tasks.inputFiles(
                 inputs,
-                { -> fontDirs },
+                { -> pdfFontDirs },
                 PathSensitivity.RELATIVE,
                 IGNORE_EMPTY_DIRECTORIES, OPTIONAL
         )
     }
 
-    /** @Deprecated Use{@link #getFontsDirs()} instead
-     *
-     * @return Pdf font directory as a file
-     * @throws {@link PdfFontDirException} if there are either multiple directories or no directory for pdf font
-     * */
-    @Deprecated
-    @ReplacedBy('getFontsDirs')
-    File getFontsDir() {
-        if (this.fontDirs.size() > 1) {
-            throw new PdfFontDirException('There is more than 1 file in the fonts directory')
-        }
-        if (this.fontDirs.empty) {
-            throw new PdfFontDirException('No directory is specified')
-        }
-        this.project.file(this.fontDirs.first())
-    }
-
-    /** @Deprecated Use{@link #setFontsDirs(java.lang.Iterable)} instead and specify the single directory
-     *
-     * Specify a directory where to load custom fonts from.
-     *
-     * This will set the {@code pdf-fontsdir} attribute
-     *
-     * @param f Directory where custom fonts can be found. anything convertible with {@link Project#file}
-     *   can be used.
-     */
-    @SuppressWarnings('UnnecessarySetter')
-    @Deprecated
-    void setFontsDir(Object f) {
-        setFontsDirs([f])
-    }
-
     /** Returns the directories or single directory for the fonts
      *
      * @return Directories for the pdf fonts
      * */
     @Internal
     FileCollection getFontsDirs() {
-        projectOperations.fsOperations.files(this.fontDirs)
+        projectOperations.fsOperations.files(this.pdfFontDirs)
     }
 
     /** Specify a directory or directories where to load custom fonts from.
@@ -113,8 +76,8 @@ class AsciidoctorPdfTask extends AbstractAsciidoctorTask {
      *   can be used.
      */
     void setFontsDirs(Iterable<Object> paths) {
-        this.fontDirs.clear()
-        this.fontDirs.addAll(paths)
+        this.pdfFontDirs.clear()
+        this.pdfFontDirs.addAll(paths)
     }
 
     /** Add files paths for the custom fonts
@@ -123,7 +86,7 @@ class AsciidoctorPdfTask extends AbstractAsciidoctorTask {
      * */
     @SuppressWarnings('UnnecessarySetter')
     void fontsDirs(Object... f) {
-        this.fontDirs.addAll(f.toList())
+        this.pdfFontDirs.addAll(f.toList())
     }
 
     /** Set the theme to be used from the {@code pdfThemes} extension.
@@ -156,32 +119,33 @@ class AsciidoctorPdfTask extends AbstractAsciidoctorTask {
         themeDescriptor?.themeName
     }
 
-    /** Selects a final process mode of PDF processing.
-     *
-     * If the system is running on Windows with a Gradle version which still has classpath leakage problems
-     * it will switch to using {@link #JAVA_EXEC}.
-     *
-     * @return Process mode to use for execution.
-     */
-    @Override
-    protected ProcessMode getFinalProcessMode() {
-        if (GradleVersion.current() <= LAST_GRADLE_WITH_CLASSPATH_LEAKAGE) {
-            if (inProcess != AbstractAsciidoctorTask.JAVA_EXEC) {
-                logger.warn 'This version of Gradle leaks snakeyaml on to worker classpaths which breaks ' +
-                        'PDF processing. Switching to JAVA_EXEC instead.'
-            }
-            AbstractAsciidoctorTask.JAVA_EXEC
-        } else {
-            super.finalProcessMode
-        }
-    }
-
-    /** The default pattern set for secondary sources.
+//    /** Selects a final process mode of PDF processing.
+//     *
+//     * If the system is running on Windows with a Gradle version which still has classpath leakage problems
+//     * it will switch to using {@link #JAVA_EXEC}.
+//     *
+//     * @return Process mode to use for execution.
+//     */
+//    @Override
+//    protected ProcessMode getFinalProcessMode() {
+//        if (GradleVersion.current() <= LAST_GRADLE_WITH_CLASSPATH_LEAKAGE) {
+//            if (inProcess != AbstractAsciidoctorTask.JAVA_EXEC) {
+//                logger.warn 'This version of Gradle leaks snakeyaml on to worker classpaths which breaks ' +
+//                        'PDF processing. Switching to JAVA_EXEC instead.'
+//            }
+//            AbstractAsciidoctorTask.JAVA_EXEC
+//        } else {
+//            super.finalProcessMode
+//        }
+//    }
+
+    /**
+     * The default pattern set for secondary sources.
      *
      * @return {@link #getDefaultSourceDocumentPattern} + `*docinfo*`.
      */
     @Override
-    protected PatternSet getDefaultSecondarySourceDocumentPattern() {
+    PatternSet getDefaultSecondarySourceDocumentPattern() {
         PatternSet ps = defaultSourceDocumentPattern
         ps.include '*-theme.y*ml'
         ps
@@ -197,32 +161,19 @@ class AsciidoctorPdfTask extends AbstractAsciidoctorTask {
      *
      * @return A collection of default attributes.
      */
-    @SuppressWarnings('UnnecessaryGetter')
     @Override
-    protected Map<String, Object> getTaskSpecificDefaultAttributes(File workingSourceDir) {
-        Map<String, Object> attrs = super.getTaskSpecificDefaultAttributes(workingSourceDir)
-
-        boolean useOldAttributes = pdfVersion.startsWith('1.5.0-alpha')
-
-        FileCollection fonts = getFontsDirs()
-        if (!fonts?.empty) {
-            attrs['pdf-fontsdir'] = fonts.asPath
-        }
-
-        File styles = themesDir
-        if (styles != null) {
-            attrs[useOldAttributes ? 'pdf-stylesdir' : 'pdf-themesdir'] = styles.absolutePath
-        }
-
-        String selectedTheme = themeName
-        if (selectedTheme != null) {
-            attrs[useOldAttributes ? 'pdf-style' : 'pdf-theme'] = selectedTheme
-        }
-
+    Map<String, ?> getTaskSpecificDefaultAttributes(File workingSourceDir) {
+        final attrs = super.getTaskSpecificDefaultAttributes(workingSourceDir)
+        final fonts = fontsDirs
+        attrs.putAll([
+                'pdf-fontsdir' : fonts.empty ? null : fonts.asPath,
+                'pdf-themesdir': themesDir?.absolutePath,
+                'pdf-theme'    : themeName
+        ].findAll { k, v -> v != null })
         attrs
     }
 
-    @CompileDynamic
+//    @CompileDynamic
     private AsciidoctorPdfThemesExtension.PdfThemeDescriptor getThemeDescriptor() {
         if (this.theme) {
             AsciidoctorPdfThemesExtension pdfThemes = project.extensions.getByType(AsciidoctorPdfThemesExtension)
@@ -231,8 +182,4 @@ class AsciidoctorPdfTask extends AbstractAsciidoctorTask {
             null
         }
     }
-
-    private String getPdfVersion() {
-        asciidoctorj.modules.pdf.version ?: project.extensions.getByType(AsciidoctorJExtension).modules.pdf.version
-    }
 }
diff --git a/jvm-pdf/src/main/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfThemesExtension.groovy b/jvm-pdf/src/main/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfThemesExtension.groovy
index a2d9d1b74..ac7177623 100644
--- a/jvm-pdf/src/main/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfThemesExtension.groovy
+++ b/jvm-pdf/src/main/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfThemesExtension.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -18,11 +18,15 @@ package org.asciidoctor.gradle.jvm.pdf
 import groovy.transform.CompileStatic
 import org.asciidoctor.gradle.base.AbstractDownloadableComponent
 import org.gradle.api.Project
-import org.ysb33r.grolifant.api.v4.StringUtils
 
-/** Easy way to configure themes for Asciidoctor PDF either as local themes or
+import java.util.concurrent.Callable
+
+/**
+ * Easy way to configure themes for Asciidoctor PDF either as local themes or
  * as downloadable.
  *
+ * @author Schalk W. Cronjé
+ *
  * @since 2.0
  */
 @CompileStatic
@@ -30,8 +34,8 @@ class AsciidoctorPdfThemesExtension extends AbstractDownloadableComponent<PdfLoc
 
     public final static String NAME = 'pdfThemes'
 
-    /** Describes tha name and location of a PDF theme.
-     *
+    /**
+     * Describes tha name and location of a PDF theme.
      */
     @SuppressWarnings('ClassName')
     static class PdfThemeDescriptor {
@@ -44,8 +48,8 @@ class AsciidoctorPdfThemesExtension extends AbstractDownloadableComponent<PdfLoc
         }
     }
 
-    /** Defines a local theme.
-     *
+    /**
+     * Defines a local theme.
      */
     @SuppressWarnings('ClassName')
     static class PdfLocalTheme {
@@ -61,7 +65,8 @@ class AsciidoctorPdfThemesExtension extends AbstractDownloadableComponent<PdfLoc
         Object themeName
     }
 
-    /** Extension for configuring PDF themes.
+    /**
+     * Extension for configuring PDF themes.
      *
      * @param project Project this extension has been associated with.
      */
@@ -69,7 +74,8 @@ class AsciidoctorPdfThemesExtension extends AbstractDownloadableComponent<PdfLoc
         super(project)
     }
 
-    /** Instantiates a component of type {@code C}.
+    /**
+     * Instantiates a component of type {@code C}.
      *
      * @param name Name of component
      * @return New component source description
@@ -81,15 +87,19 @@ class AsciidoctorPdfThemesExtension extends AbstractDownloadableComponent<PdfLoc
         theme
     }
 
-    /** Create a closure that will convert an instance of a {@code C} into a {@code S}.
+    /**
+     * Create a closure that will convert an instance of a {@link PdfLocalTheme} into a {@link PdfThemeDescriptor}.
      *
      * @param theme Component to be converted.
      * @return Converting closure.
      */
     @Override
-    protected Closure convertible(PdfLocalTheme theme) {
+    protected Callable<PdfThemeDescriptor> convertible(PdfLocalTheme theme) {
         return { ->
-            new PdfThemeDescriptor(StringUtils.stringize(theme.themeName), project.file(theme.themeDir))
+            new PdfThemeDescriptor(
+                    projectOperations.stringTools.stringize(theme.themeName),
+                    projectOperations.fsOperations.file(theme.themeDir)
+            )
         }
     }
 
diff --git a/jvm-pdf/src/main/groovy/org/asciidoctor/gradle/jvm/pdf/PdfFontDirException.groovy b/jvm-pdf/src/main/groovy/org/asciidoctor/gradle/jvm/pdf/PdfFontDirException.groovy
index e7dd3c568..2ac2b5558 100644
--- a/jvm-pdf/src/main/groovy/org/asciidoctor/gradle/jvm/pdf/PdfFontDirException.groovy
+++ b/jvm-pdf/src/main/groovy/org/asciidoctor/gradle/jvm/pdf/PdfFontDirException.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/jvm-pdf/src/test/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfThemeExtensionSpec.groovy b/jvm-pdf/src/test/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfThemeExtensionSpec.groovy
index d5d465636..ab23aaf47 100644
--- a/jvm-pdf/src/test/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfThemeExtensionSpec.groovy
+++ b/jvm-pdf/src/test/groovy/org/asciidoctor/gradle/jvm/pdf/AsciidoctorPdfThemeExtensionSpec.groovy
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2023 the original author or authors.
+ * Copyright 2013-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -106,7 +106,8 @@ class AsciidoctorPdfThemeExtensionSpec extends Specification {
     }
 
     File determineUnpackedDir(String cacheSubDir, String pattern) {
-        File baseDir = project.file("${project.buildDir}/${cacheSubDir}/foo/bar/${pattern}")
-        FileUtils.listDirs(baseDir)[0]
+        File baseDir = project.file("${project.buildDir}/cloud-archives/${cacheSubDir}/foo/bar/${pattern}")
+        final x = projectOperations.fsOperations.listDirs(baseDir)[0]
+        x
     }
 }
\ No newline at end of file
diff --git a/jvm/build.gradle b/jvm/build.gradle
index 8c4a4843c..f71bb154d 100644
--- a/jvm/build.gradle
+++ b/jvm/build.gradle
@@ -81,6 +81,7 @@ tasks.named('check') {
     dependsOn remoteTest
 }
 
+// TODO: Use configurePlugin instead
 gradlePlugin {
     plugins {
         basePlugin {
diff --git a/jvm/src/intTest/groovy/org/asciidoctor/gradle/internal/FunctionalSpecification.groovy b/jvm/src/intTest/groovy/org/asciidoctor/gradle/internal/FunctionalSpecification.groovy
index 973c85f4a..220094faf 100644
--- a/jvm/src/intTest/groovy/org/asciidoctor/gradle/internal/FunctionalSpecification.groovy
+++ b/jvm/src/intTest/groovy/org/asciidoctor/gradle/internal/FunctionalSpecification.groovy
@@ -21,7 +21,6 @@ import org.asciidoctor.gradle.testfixtures.DslType
 import org.asciidoctor.gradle.testfixtures.FunctionalTestFixture
 import org.asciidoctor.gradle.testfixtures.FunctionalTestSetup
 import org.gradle.testkit.runner.GradleRunner
-import spock.lang.Shared
 import spock.lang.Specification
 import spock.lang.TempDir
 
@@ -44,11 +43,11 @@ class FunctionalSpecification extends Specification implements FunctionalTestFix
 
     void setup() {
         projectDir.mkdirs()
-        testKitDir = new File(testProjectDir,".testkit-${UUID.randomUUID().toString()}")
+        testKitDir = new File(testProjectDir, ".testkit-${UUID.randomUUID()}")
     }
 
     void cleanup() {
-        if(testKitDir && testKitDir.exists()) {
+        if (testKitDir && testKitDir.exists()) {
             testKitDir.deleteDir()
         }
     }
diff --git a/jvm/src/intTest/groovy/org/asciidoctor/gradle/jvm/AsciidoctorTaskCachingFunctionalSpec.groovy b/jvm/src/intTest/groovy/org/asciidoctor/gradle/jvm/AsciidoctorTaskCachingFunctionalSpec.groovy
index 19148dcd9..74062f778 100644
--- a/jvm/src/intTest/groovy/org/asciidoctor/gradle/jvm/AsciidoctorTaskCachingFunctionalSpec.groovy
+++ b/jvm/src/intTest/groovy/org/asciidoctor/gradle/jvm/AsciidoctorTaskCachingFunctionalSpec.groovy
@@ -37,7 +37,6 @@ class AsciidoctorTaskCachingFunctionalSpec extends FunctionalSpecification
     public static final String DEFAULT_OUTPUT_FILE = 'build/docs/asciidoc/html5/sample.html'
     public static final String DOCBOOK_OUTPUT_FILE = 'build/docs/asciidoc/docbook/sample.xml'
 
-
     void setup() {
         setupCache()
         createTestProject()
@@ -72,36 +71,36 @@ class AsciidoctorTaskCachingFunctionalSpec extends FunctionalSpecification
         fileInRelocatedDirectory(DOCBOOK_OUTPUT_FILE).exists()
     }
 
-    @Issue('https://github.com/asciidoctor/asciidoctor-gradle-plugin/issues/671')
-    void "asciidoctor task is cacheable and relocatable when gemPaths is configured"() {
-        given:
-        getBuildFile("""
-            asciidoctorj {
-                gemPaths 'gems1', 'gems2'
-            }
-
-            asciidoctor {
-                sourceDir 'src/docs/asciidoc'
-                
-                outputOptions {
-                    backends 'html5', 'docbook'
-                }
-            }
-        """)
-
-        when:
-        assertDefaultTaskExecutes()
-
-        then:
-        outputFile.exists()
-
-        when:
-        assertDefaultTaskIsCachedAndRelocatable()
-
-        then:
-        outputFile.exists()
-        outputFileInRelocatedDirectory.exists()
-    }
+//    @Issue('https://github.com/asciidoctor/asciidoctor-gradle-plugin/issues/671')
+//    void "asciidoctor task is cacheable and relocatable when gemPaths is configured"() {
+//        given:
+//        getBuildFile("""
+//            asciidoctorj {
+//                gemPaths 'gems1', 'gems2'
+//            }
+//
+//            asciidoctor {
+//                sourceDir 'src/docs/asciidoc'
+//
+//                outputOptions {
+//                    backends 'html5', 'docbook'
+//                }
+//            }
+//        """)
+//
+//        when:
+//        assertDefaultTaskExecutes()
+//
+//        then:
+//        outputFile.exists()
+//
+//        when:
+//        assertDefaultTaskIsCachedAndRelocatable()
+//
+//        then:
+//        outputFile.exists()
+//        outputFileInRelocatedDirectory.exists()
+//    }
 
     void "Asciidoctor task is cached when only output directory is changed"() {
         given:
diff --git a/jvm/src/main/groovy/org/asciidoctor/gradle/internal/DefaultAsciidoctorJModules.groovy b/jvm/src/main/groovy/org/asciidoctor/gradle/internal/DefaultAsciidoctorJModules.groovy
index e8a3e6d04..d18b3d25d 100644
--- a/jvm/src/main/groovy/org/asciidoctor/gradle/internal/DefaultAsciidoctorJModules.groovy
+++ b/jvm/src/main/groovy/org/asciidoctor/gradle/internal/DefaultAsciidoctorJModules.groovy
@@ -44,6 +44,8 @@ class DefaultAsciidoctorJModules implements AsciidoctorJModules {
     private final AsciidoctorModuleDefinition groovyDsl
     private Action<AsciidoctorJModules> updater
 
+    // TODO: Remove this warning - it is only there temporarily.
+    @SuppressWarnings('UnusedMethodParameter')
     DefaultAsciidoctorJModules(
             ProjectOperations po,
             AsciidoctorJExtension asciidoctorjs,
diff --git a/jvm/src/main/groovy/org/asciidoctor/gradle/internal/ExecutorConfiguration.groovy b/jvm/src/main/groovy/org/asciidoctor/gradle/internal/ExecutorConfiguration.groovy
index b67d772f1..fd3c7d62b 100644
--- a/jvm/src/main/groovy/org/asciidoctor/gradle/internal/ExecutorConfiguration.groovy
+++ b/jvm/src/main/groovy/org/asciidoctor/gradle/internal/ExecutorConfiguration.groovy
@@ -38,7 +38,6 @@ class ExecutorConfiguration implements Serializable, Cloneable {
     List<Pattern> fatalMessagePatterns
 
     String backendName
-    String gemPath
 
     boolean logDocuments
     boolean copyResources
@@ -66,7 +65,6 @@ File locations:
   baseDir = ${baseDir}
 
 JRuby:
-  GEMPATH = ${gemPath}
   requires = ${requires}
 
 Asciidoctor:
diff --git a/jvm/src/main/groovy/org/asciidoctor/gradle/jvm/AbstractAsciidoctorTask.groovy b/jvm/src/main/groovy/org/asciidoctor/gradle/jvm/AbstractAsciidoctorTask.groovy
index 836c5d776..e91ba916a 100644
--- a/jvm/src/main/groovy/org/asciidoctor/gradle/jvm/AbstractAsciidoctorTask.groovy
+++ b/jvm/src/main/groovy/org/asciidoctor/gradle/jvm/AbstractAsciidoctorTask.groovy
@@ -43,10 +43,13 @@ import org.gradle.api.artifacts.ConfigurationContainer
 import org.gradle.api.artifacts.Dependency
 import org.gradle.api.file.FileCollection
 import org.gradle.api.provider.Property
+import org.gradle.api.provider.Provider
 import org.gradle.api.tasks.Classpath
 import org.gradle.api.tasks.Input
 import org.gradle.api.tasks.Internal
 import org.gradle.api.tasks.Nested
+import org.gradle.api.tasks.TaskProvider
+import org.gradle.api.tasks.bundling.Jar
 import org.gradle.process.JavaForkOptions
 import org.gradle.workers.WorkerExecutor
 import org.ysb33r.grolifant.api.core.jvm.ExecutionMode
@@ -97,6 +100,7 @@ class AbstractAsciidoctorTask extends AbstractJvmModelExecTask<AsciidoctorJvmExe
     private final File execConfigurationDataFile
     private final Function<List<Dependency>, Configuration> detachedConfigurationCreator
     private final Property<FileCollection> jvmClasspath
+    private final List<Provider<File>> gemJarProviders = []
 
     @Delegate
     private final DefaultAsciidoctorFileOperations asciidoctorTaskFileOperations
@@ -105,7 +109,7 @@ class AbstractAsciidoctorTask extends AbstractJvmModelExecTask<AsciidoctorJvmExe
     private final AsciidoctorTaskWorkspacePreparation workspacePreparation
 
     @Delegate
-    private final DefaultAsciidoctorOutputOptions outputOptions
+    private final DefaultAsciidoctorOutputOptions asciidoctorOutputOptions
 
     @Delegate
     private final AsciidoctorTaskBaseDirConfiguration baseDirConfiguration
@@ -298,12 +302,13 @@ class AbstractAsciidoctorTask extends AbstractJvmModelExecTask<AsciidoctorJvmExe
     @Classpath
     @SuppressWarnings('Instanceof')
     FileCollection getConfigurations() {
-        FileCollection precompiledExtensions = findDependenciesInExtensions()
+        final precompiledExtensions = findDependenciesInExtensions()
         FileCollection fc = this.asciidocConfigurations.inject(asciidoctorj.configuration) {
             FileCollection seed, Object it ->
                 seed + projectOperations.configurations.asConfiguration(it)
         }
-        precompiledExtensions ? fc + precompiledExtensions : fc
+        final gjp = projectOperations.fsOperations.files([gemJarProviders, fc])
+        precompiledExtensions ? gjp + precompiledExtensions : gjp
     }
 
     /** Override any existing configurations except the ones available via the {@code asciidoctorj} task extension.
@@ -346,15 +351,42 @@ class AbstractAsciidoctorTask extends AbstractJvmModelExecTask<AsciidoctorJvmExe
     }
 
     /**
-     * Additional locations to consider when GEMs are loaded by AsciidoctorJ or JRuby.
+     * Adds a Jar of GEMs to the classpath.
      *
-     * @return The additional GEM locations.
+     * @param gemJar Provider to a {@link Jar} task which contain GEMs
      *
      * @since 4.0
      */
-    @Internal
-    String getGemPath() {
-        asciidoctorj.asGemPath()
+    void withGemJar(TaskProvider<Jar> gemJar) {
+        dependsOn(gemJar)
+        this.gemJarProviders.add(gemJar.map { it.archiveFile.get().asFile })
+    }
+
+    /**
+     * Adds a Jar of GEMs to the classpath.
+     *
+     * @param gemJar name of a {@link Jar} task which contain GEMs.
+     *
+     * @since 4.0
+     */
+    void withGemJar(String taskName) {
+        dependsOn(taskName)
+        final gemJar = project.tasks.named(taskName, Jar)
+        this.gemJarProviders.add(gemJar.map { it.archiveFile.get().asFile })
+    }
+
+    /**
+     * Adds a directory to the classpath. THe directory will contain unpacked GEMs.
+     *
+     * @param gemPath A provider to a directory containing unpakcing GEMs.
+     *
+     * @param builtBy THe name of the task that prepares this directory.
+     *
+     * @since 4.0
+     */
+    void withGemPath(Provider<File> gemPath, String builtBy) {
+        dependsOn(builtBy)
+        this.gemJarProviders.add(gemPath)
     }
 
     /**
@@ -428,7 +460,11 @@ class AbstractAsciidoctorTask extends AbstractJvmModelExecTask<AsciidoctorJvmExe
                 this.asciidoctorTaskFileOperations,
                 this.asciidoctorTaskFileOperations
         )
-        this.outputOptions = new DefaultAsciidoctorOutputOptions(projectOperations, name, asciidoctorTaskFileOperations)
+        this.asciidoctorOutputOptions = new DefaultAsciidoctorOutputOptions(
+                projectOperations,
+                name,
+                asciidoctorTaskFileOperations
+        )
         this.baseDirConfiguration = new DefaultAsciidoctorBaseDirConfiguration(project, this)
         this.asciidoctorj = extensions.create(AsciidoctorJExtension.NAME, AsciidoctorJExtension, this)
         this.projectDir = project.projectDir
@@ -443,7 +479,7 @@ class AbstractAsciidoctorTask extends AbstractJvmModelExecTask<AsciidoctorJvmExe
         }.curry(project.configurations) as Function<List<Dependency>, Configuration>
 
         inputs.files(this.asciidoctorj.configuration)
-        inputs.files { asciidoctorj.gemPaths }.withPathSensitivity(RELATIVE)
+        inputs.files { gemJarProviders }.withPathSensitivity(RELATIVE)
         inputs.property 'backends', { -> backends() }
         inputs.property 'asciidoctorj-version', { -> asciidoctorj.version }
         inputs.property 'jruby-version', { -> asciidoctorj.jrubyVersion ?: '' }
@@ -548,10 +584,9 @@ class AbstractAsciidoctorTask extends AbstractJvmModelExecTask<AsciidoctorJvmExe
                 ),
                 backendName: backendName,
                 logDocuments: logDocuments,
-                gemPath: gemPath,
                 fatalMessagePatterns: asciidoctorj.fatalWarnings,
                 asciidoctorExtensions: (asciidoctorJExtensions.findAll { !(it instanceof Dependency) }),
-                requires: requires,
+                requires: asciidoctorj.requires,
                 copyResources: copyResources.present &&
                         (copyResources.get().empty || backendName in copyResources.get()),
                 executorLogLevel: ExecutorUtils.getExecutorLogLevel(asciidoctorj.logLevel),
@@ -579,17 +614,6 @@ class AbstractAsciidoctorTask extends AbstractJvmModelExecTask<AsciidoctorJvmExe
 //        this.javaForkOptions.copyTo(pfo)
 //    }
 
-    /** Allow a task to enhance additional '{@code requires}'
-     *
-     * The default implementation will add a special script to deal with verbose mode.
-     *
-     * @return The final set of '{@code requires}'
-     */
-    @Internal
-    protected List<String> getRequires() {
-        asciidoctorj.requires
-    }
-
     @Nested
     protected AsciidoctorTaskFileOperations getAsciidoctorTaskFileOperations() {
         this.asciidoctorTaskFileOperations
@@ -601,8 +625,8 @@ class AbstractAsciidoctorTask extends AbstractJvmModelExecTask<AsciidoctorJvmExe
     }
 
     @Nested
-    protected AsciidoctorTaskOutputOptions getOutputOptions() {
-        this.outputOptions
+    protected AsciidoctorTaskOutputOptions getAsciidoctorOutputOptions() {
+        this.asciidoctorOutputOptions
     }
 
     @Nested
@@ -643,34 +667,6 @@ class AbstractAsciidoctorTask extends AbstractJvmModelExecTask<AsciidoctorJvmExe
         mapping
     }
 
-//    /** Selects a final process mode.
-//     *
-//     * Some incompatibilities can cause certain process mode to fail given a combination of factors.
-//     *
-//     * Task implementations can override this method to select a safe process mode, than the one provided by the
-//     * build script author. The default implementation will simply return whatever what was configured, except in the
-//     * case for Gradle 4.3 or older in which case it will always return {@link #JAVA_EXEC}.
-//     *
-//     * @return Process mode to use for execution.
-//     */
-//    @Internal
-//    protected ExecutionMode getFinalProcessMode() {
-//        if (inProcess != JAVA_EXEC && GradleVersion.current() < GradleVersion.version(('4.3'))) {
-//            logger.warn('Gradle API classpath leakage will cause issues with Gradle < 4.3. ' +
-//                    'Switching to JAVA_EXEC instead.')
-//            JAVA_EXEC
-//        } else {
-//            this.inProcess
-//        }
-//    }
-//    private Workspace prepareWorkspace(Optional<String> lang) {
-//        if (lang.present) {
-//            workspacePreparation.prepareWorkspace(lang.get())
-//        } else {
-//            workspacePreparation.prepareWorkspace()
-//        }
-//    }
-//
     private List<Optional<String>> getLanguagesAsOptionals() {
         if (this.languages.empty) {
             [Optional.empty() as Optional<String>]
@@ -681,99 +677,6 @@ class AbstractAsciidoctorTask extends AbstractJvmModelExecTask<AsciidoctorJvmExe
         }
     }
 
-//    private Map<String, ExecutorConfiguration> runWithWorkers(
-//            final File workingSourceDir,
-//            final Set<File> sourceFiles,
-//            Optional<String> lang
-//    ) {
-//        FileCollection asciidoctorClasspath = configurations
-//        logger.info "Running AsciidoctorJ with workers. Classpath = ${asciidoctorClasspath.files}"
-//
-//        Map<String, ExecutorConfiguration> executorConfigurations = getExecutorConfigurations(
-//                workingSourceDir,
-//                sourceFiles,
-//                lang
-//        )
-//
-//        if (parallelMode) {
-//            WorkQueue queue = getWorkQueue(asciidoctorClasspath)
-//            executorConfigurations.each { String configName, ExecutorConfiguration executorConfiguration ->
-//                copyResourcesByBackend(executorConfiguration, lang)
-//                queue.submit(AsciidoctorJExecuterWorker) { params ->
-//                    params.extensionConfigurationContainer =
-//                            new ExecutorConfigurationContainer(executorConfiguration)
-//                }
-//            }
-//        } else {
-//            copyResourcesByBackend(executorConfigurations.values(), lang)
-//            getWorkQueue(asciidoctorClasspath).submit(AsciidoctorJExecuterWorker) { params ->
-//                params.extensionConfigurationContainer =
-//                        new ExecutorConfigurationContainer(executorConfigurations.values())
-//            }
-//        }
-//        executorConfigurations
-//    }
-
-//    private WorkQueue getWorkQueue(FileCollection asciidoctorClasspath) {
-//        IN_PROCESS ?
-//                worker.classLoaderIsolation(configureClassloaderIsolatedWorker(asciidoctorClasspath)) :
-//                worker.processIsolation(configureProcessIsolatedWorker(asciidoctorClasspath))
-//    }
-//
-//    private Closure configureClassloaderIsolatedWorker(FileCollection asciidoctorClasspath) {
-//        return { ClassLoaderWorkerSpec spec ->
-//            spec.classpath.from(asciidoctorClasspath)
-//        }
-//    }
-//
-//    private Closure configureProcessIsolatedWorker(FileCollection asciidoctorClasspath) {
-//        return { ProcessWorkerSpec spec ->
-//            spec.classpath.from(asciidoctorClasspath)
-//            configureForkOptions(spec.forkOptions)
-//        }
-//    }
-
-//    private Map<String, ExecutorConfiguration> runWithJavaExec(
-//            final File workingSourceDir,
-//            final Set<File> sourceFiles,
-//            Optional<String> lang
-//    ) {
-//        FileCollection javaExecClasspath = JavaExecUtils.getJavaExecClasspath(
-//                project,
-//                configurations,
-//                asciidoctorj.injectInternalGuavaJar
-//        )
-//        Map<String, ExecutorConfiguration> executorConfigurations = getExecutorConfigurations(
-//                workingSourceDir,
-//                sourceFiles,
-//                lang
-//        )
-//        File execConfigurationData = JavaExecUtils.writeExecConfigurationData(this, executorConfigurations.values())
-//        copyResourcesByBackend(executorConfigurations.values(), lang)
-//
-//        logger.debug("Serialised AsciidoctorJ configuration to ${execConfigurationData}")
-//        logger.info "Running AsciidoctorJ instance with classpath ${javaExecClasspath.files}"
-//
-//        try {
-//            projectOperations.javaexec { JavaExecSpec jes ->
-//                configureForkOptions(jes)
-//                logger.debug "Running AsciidoctorJ instance with environment: ${jes.environment}"
-//                jes.with {
-//                    setExecClass(jes, AsciidoctorJavaExec.canonicalName)
-//                    classpath = javaExecClasspath
-//                    args execConfigurationData.absolutePath
-//                }
-//            }
-//        } catch (GradleException e) {
-//            throw new AsciidoctorRemoteExecutionException(
-//                    'Remote Asciidoctor process failed to complete successfully',
-//                    e
-//            )
-//        }
-//
-//        executorConfigurations
-//    }
-
     private void copyResourcesByExecutorConfiguration(
             Iterable<ExecutorConfiguration> executorConfigurations,
             Optional<String> lang
diff --git a/jvm/src/main/groovy/org/asciidoctor/gradle/jvm/AsciidoctorJExtension.groovy b/jvm/src/main/groovy/org/asciidoctor/gradle/jvm/AsciidoctorJExtension.groovy
index ab7c842d2..8d986c72a 100644
--- a/jvm/src/main/groovy/org/asciidoctor/gradle/jvm/AsciidoctorJExtension.groovy
+++ b/jvm/src/main/groovy/org/asciidoctor/gradle/jvm/AsciidoctorJExtension.groovy
@@ -27,10 +27,7 @@ import org.gradle.api.*
 @java.lang.SuppressWarnings('NoWildcardImports')
 import org.gradle.api.artifacts.*
 import org.gradle.api.artifacts.dsl.DependencyHandler
-import org.gradle.api.file.FileCollection
 import org.gradle.api.logging.LogLevel
-import org.ysb33r.grolifant.api.core.LegacyLevel
-import org.ysb33r.grolifant.api.core.OperatingSystem
 
 import java.util.concurrent.Callable
 import java.util.function.BiConsumer
@@ -65,11 +62,11 @@ class AsciidoctorJExtension extends AbstractImplementationEngineExtension {
     private static final String ASCIIDOCTORJ_LEANPUB_DEPENDENCY = "${ASCIIDOCTORJ_GROUP}:asciidoctor-leanpub-markdown"
     private static final String JRUBY_COMPLETE_DEPENDENCY = JavaExecUtils.JRUBY_COMPLETE_DEPENDENCY
     private static final String ASCIIDOCTOR_DEPENDENCY_PROPERTY_NAME = 'asciidoctorj'
-    private static final OperatingSystem OS = OperatingSystem.current()
-    // TODO: Kill this off
-    private static final boolean GUAVA_REQUIRED_FOR_EXTERNALS = !LegacyLevel.PRE_4_8
     private static final String CONFIGURATION_NAME = "__\$\$${NAME}\$\$__"
 
+    // TODO: Kill this off
+//    private static final boolean GUAVA_REQUIRED_FOR_EXTERNALS = !LegacyLevel.PRE_4_8
+
     private static final BiConsumer<DependencyResolveDetails, Callable<String>> DRD_VERSION_RESOLVER = {
         DependencyResolveDetails drd, Callable<String> versionResolver ->
             drd.useVersion(versionResolver.call())
@@ -79,24 +76,22 @@ class AsciidoctorJExtension extends AbstractImplementationEngineExtension {
     private final Map<String, Object> options = [:]
     private final List<Object> jrubyRequires = []
     private final List<Object> asciidoctorExtensions = []
-    private final List<Object> gemPaths = []
+//    private final List<Object> gemPaths = []
     private final List<Object> warningsAsErrors = []
     private final DefaultAsciidoctorJModules modules
     private final Configuration publicConfiguration
     private final Configuration privateConfiguration
     private final BiFunction<String, Closure, Dependency> dependencyCreator
     private final Function<Project, Dependency> projectDependency
-
     private Object version
     private Optional<Object> jrubyVersion
-    private Boolean injectGuavaJar
     private boolean onlyTaskOptions = false
-    private boolean onlyTaskRequires = false
     private boolean onlyTaskExtensions = false
-    private boolean onlyTaskGems = false
     private boolean onlyTaskWarnings = false
-
     private LogLevel logLevel
+//    private Boolean injectGuavaJar
+    private boolean onlyTaskRequires = false
+//    private boolean onlyTaskGems = false
 
     /** Attach extension to a project.
      *
@@ -266,56 +261,57 @@ class AsciidoctorJExtension extends AbstractImplementationEngineExtension {
         ~/include file not found/
     }
 
-    /* -------------------------
-       tag::extension-property[]
-       gemPaths:: One or more gem installation directories (separated by the system path separator).
-         Use `gemPaths` to append. Use `setGemPaths` or `gemPaths=['path1','path2']` to overwrite.
-         Use `asGemPath` to obtain a path string, separated by platform-specific separator.
-         Type: `FileCollection`, but any collection of objects convertible with `project.files` can be passed
-         Default: empty
-       end::extension-property[]
-       ------------------------- */
-
-    /** Returns the list of paths to be used for {@code GEM_HOME}
-     *
-     */
-    FileCollection getGemPaths() {
-        if (!task || onlyTaskGems) {
-            projectOperations.fsOperations.files(this.gemPaths)
-        } else {
-            projectOperations.fsOperations.files(this.gemPaths).from(extFromProject.gemPaths)
-        }
-    }
-
-    /** Sets a new list of GEM paths to be used.
-     *
-     * @param paths Paths resolvable by {@ocde project.files}
-     */
-    void setGemPaths(Iterable<Object> paths) {
-        this.gemPaths.clear()
-        this.gemPaths.addAll(paths)
-
-        if (task) {
-            this.onlyTaskGems = true
-        }
-    }
-
-    /** Adds more paths for discovering GEMs.
-     *
-     * @param f Path objects that can be be converted with {@code project.file}.
-     */
-    void gemPaths(Object... f) {
-        this.gemPaths.addAll(f)
-    }
-
-    /** Returns the list of paths to be used for GEM installations in a format that is
-     * suitable for assignment to {@code GEM_HOME}
-     *
-     * Calling this will cause gemPath to be resolved immediately.
-     */
-    String asGemPath() {
-        getGemPaths().files*.toString().join(OS.pathSeparator)
-    }
+//    /* -------------------------
+//       tag::extension-property[]
+//       gemPaths:: One or more gem installation directories (separated by the system path separator).
+//         Use `gemPaths` to append. Use `setGemPaths` or `gemPaths=['path1','path2']` to overwrite.
+//         Use `asGemPath` to obtain a path string, separated by platform-specific separator.
+//         Type: `FileCollection`, but any collection of objects convertible with `project.files` can be passed
+//         Default: empty
+//       end::extension-property[]
+//       ------------------------- */
+//
+//    /** Returns the list of paths to be used for {@code GEM_HOME}
+//     *
+//     */
+//    FileCollection getGemPaths() {
+//        if (!task || onlyTaskGems) {
+//            projectOperations.fsOperations.files(this.gemPaths)
+//        } else {
+//            projectOperations.fsOperations.files(this.gemPaths).from(extFromProject.gemPaths)
+//        }
+//    }
+//
+//    /** Sets a new list of GEM paths to be used.
+//     *
+//     * @param paths Paths resolvable by {@ocde project.files}
+//     */
+//    void setGemPaths(Iterable<Object> paths) {
+//        this.gemPaths.clear()
+//        this.gemPaths.addAll(paths)
+//
+//        if (task) {
+//            this.onlyTaskGems = true
+//        }
+//    }
+//
+//    /** Adds more paths for discovering GEMs.
+//     *
+//     * @param f Path objects that can be be converted with {@code project.file}.
+//     */
+//    void gemPaths(Object... f) {
+//        this.gemPaths.addAll(f)
+//    }
+//
+//    /**
+//     * Returns the list of paths to be used for GEM installations in a format that is
+//     * suitable for assignment to {@code GEM_HOME}
+//     *
+//     * Calling this will cause gemPath to be resolved immediately.
+//     */
+//    String asGemPath() {
+//        getGemPaths().files*.toString().join(OS.pathSeparator)
+//    }
 
     /* -------------------------
        tag::extension-property[]
@@ -580,30 +576,30 @@ class AsciidoctorJExtension extends AbstractImplementationEngineExtension {
         this.version = v
     }
 
-    /** Whether the Guava JAR that ships with the Gradle distribution should be injected into the
-     * classpath for external AsciidoctorJ processes.
-     *
-     * If not set previously via {@link #setInjectInternalGuavaJar} then a default version depending of the version of
-     * the Gradle distribution will be used.
-     *
-     * @return {@code true} if JAR should be injected.
-     */
-    boolean getInjectInternalGuavaJar() {
-        if (task) {
-            this.injectGuavaJar == null ? extFromProject.injectInternalGuavaJar : this.injectGuavaJar
-        } else {
-            this.injectGuavaJar == null ? GUAVA_REQUIRED_FOR_EXTERNALS : this.injectGuavaJar
-        }
-    }
-
-    /** Whether the Guava JAR that ships with the Gradle distribution should be injected into the
-     * classpath for external AsciidoctorJ processes.
-     *
-     * @param inject {@code true} if JAR should be injected.
-     */
-    void setInjectInternalGuavaJar(boolean inject) {
-        this.injectGuavaJar = inject
-    }
+//    /** Whether the Guava JAR that ships with the Gradle distribution should be injected into the
+//     * classpath for external AsciidoctorJ processes.
+//     *
+//     * If not set previously via {@link #setInjectInternalGuavaJar} then a default version depending of the version of
+//     * the Gradle distribution will be used.
+//     *
+//     * @return {@code true} if JAR should be injected.
+//     */
+//    boolean getInjectInternalGuavaJar() {
+//        if (task) {
+//            this.injectGuavaJar == null ? extFromProject.injectInternalGuavaJar : this.injectGuavaJar
+//        } else {
+//            this.injectGuavaJar == null ? GUAVA_REQUIRED_FOR_EXTERNALS : this.injectGuavaJar
+//        }
+//    }
+
+//    /** Whether the Guava JAR that ships with the Gradle distribution should be injected into the
+//     * classpath for external AsciidoctorJ processes.
+//     *
+//     * @param inject {@code true} if JAR should be injected.
+//     */
+//    void setInjectInternalGuavaJar(boolean inject) {
+//        this.injectGuavaJar = inject
+//    }
 
     /**
      * Returns a runConfiguration of the configured AsciidoctorJ dependencies.
diff --git a/jvm/src/main/groovy/org/asciidoctor/gradle/jvm/AsciidoctorTask.groovy b/jvm/src/main/groovy/org/asciidoctor/gradle/jvm/AsciidoctorTask.groovy
index 7e6b4af47..66abfb77b 100755
--- a/jvm/src/main/groovy/org/asciidoctor/gradle/jvm/AsciidoctorTask.groovy
+++ b/jvm/src/main/groovy/org/asciidoctor/gradle/jvm/AsciidoctorTask.groovy
@@ -21,6 +21,7 @@ import org.gradle.api.Action
 import org.gradle.api.tasks.CacheableTask
 import org.gradle.api.tasks.util.PatternSet
 import org.gradle.workers.WorkerExecutor
+import org.ysb33r.grolifant.api.core.ClosureUtils
 
 import javax.inject.Inject
 
@@ -61,7 +62,7 @@ class AsciidoctorTask extends AbstractAsciidoctorTask {
      * @param cfg Closure which will delegate to a {@link org.asciidoctor.gradle.base.OutputOptions} instance.
      */
     void outputOptions(@DelegatesTo(OutputOptions) Closure cfg) {
-        outputOptions.configureOutputOptions(cfg)
+        ClosureUtils.configureItem(outputOptions, cfg)
     }
 
     /** Configures output options for this task.
@@ -70,13 +71,14 @@ class AsciidoctorTask extends AbstractAsciidoctorTask {
      *   to configure.
      */
     void outputOptions(Action<OutputOptions> cfg) {
-        outputOptions.configureOutputOptions(cfg)
+        cfg.execute(outputOptions)
     }
 
     @Inject
     AsciidoctorTask(WorkerExecutor we) {
         super(we)
         final String taskPrefix = 'asciidoctor'
+        executionMode = JAVA_EXEC // TODO: Remove this as it is just for testing
         String folderName
         if (name.startsWith(taskPrefix)) {
             folderName = name.replaceFirst(taskPrefix, 'asciidoc')
diff --git a/jvm/src/main/groovy/org/asciidoctor/gradle/remote/AsciidoctorJavaExec.groovy b/jvm/src/main/groovy/org/asciidoctor/gradle/remote/AsciidoctorJavaExec.groovy
index f6c2be8b4..97688b4aa 100644
--- a/jvm/src/main/groovy/org/asciidoctor/gradle/remote/AsciidoctorJavaExec.groovy
+++ b/jvm/src/main/groovy/org/asciidoctor/gradle/remote/AsciidoctorJavaExec.groovy
@@ -116,15 +116,13 @@ class AsciidoctorJavaExec extends ExecutorBase {
         extensionRegistry.registerExtensionsWith((Asciidoctor) asciidoctor)
     }
 
-    private Asciidoctor getAsciidoctorInstance() {
-        String combinedGemPath = runConfigurations*.gemPath.findAll { it }.join(File.pathSeparator)
-        boolean noGemPath = combinedGemPath.empty || combinedGemPath == File.pathSeparator
-        noGemPath ? create() : create(combinedGemPath)
-    }
-
     private void addRequires(Asciidoctor asciidoctor) {
         runConfigurations.each { runConfiguration ->
             asciidoctor.requireLibraries(runConfiguration.requires)
         }
     }
+
+    private Asciidoctor getAsciidoctorInstance() {
+        create()
+    }
 }
diff --git a/jvm/src/main/groovy/org/asciidoctor/gradle/remote/AsciidoctorWorkerExecutor.groovy b/jvm/src/main/groovy/org/asciidoctor/gradle/remote/AsciidoctorWorkerExecutor.groovy
index 519eeb6dd..27fc226b5 100644
--- a/jvm/src/main/groovy/org/asciidoctor/gradle/remote/AsciidoctorWorkerExecutor.groovy
+++ b/jvm/src/main/groovy/org/asciidoctor/gradle/remote/AsciidoctorWorkerExecutor.groovy
@@ -65,12 +65,10 @@ class AsciidoctorWorkerExecutor implements WorkerAppExecutor<AsciidoctorWorkerPa
 
     @SuppressWarnings('CatchThrowable')
     private void runSingle(ExecutorConfiguration runConfiguration) {
-        Asciidoctor asciidoctor = create(
-                runConfiguration.gemPath.empty ? null : runConfiguration.gemPath
-        )
+        Asciidoctor asciidoctor = create()
 
         runConfiguration.with {
-            asciidoctor.requireLibraries(requires)
+            asciidoctor.requireLibraries(runConfiguration.requires)
             if (asciidoctorExtensions?.size()) {
                 registerExtensions(asciidoctor, asciidoctorExtensions)
             }
@@ -109,4 +107,10 @@ class AsciidoctorWorkerExecutor implements WorkerAppExecutor<AsciidoctorWorkerPa
         }
         extensionRegistry.registerExtensionsWith((Asciidoctor) asciidoctor)
     }
+
+//    private void addRequires(Asciidoctor asciidoctor) {
+//        runConfigurations.each { runConfiguration ->
+//            asciidoctor.requireLibraries(runConfiguration.requires)
+//        }
+//    }
 }
diff --git a/jvm/src/remoteTest/groovy/org/asciidoctor/gradle/remote/AsciidoctorJavaExecSpec.groovy b/jvm/src/remoteTest/groovy/org/asciidoctor/gradle/remote/AsciidoctorJavaExecSpec.groovy
index f3668a294..cf2233c44 100644
--- a/jvm/src/remoteTest/groovy/org/asciidoctor/gradle/remote/AsciidoctorJavaExecSpec.groovy
+++ b/jvm/src/remoteTest/groovy/org/asciidoctor/gradle/remote/AsciidoctorJavaExecSpec.groovy
@@ -40,7 +40,7 @@ class AsciidoctorJavaExecSpec extends RemoteSpecification {
         ExecutorConfigurationContainer ecc = getContainerMultipleEntries(
             asciidoc.src,
             asciidoc.outputDir,
-            asciidoc.gemPath
+            null // asciidoc.gemPath
         )
         ecc.toFile(executionData, ecc.configurations)
 
diff --git a/jvm/src/remoteTest/groovy/org/asciidoctor/gradle/remote/internal/RemoteSpecification.groovy b/jvm/src/remoteTest/groovy/org/asciidoctor/gradle/remote/internal/RemoteSpecification.groovy
index dec699174..d2570b767 100644
--- a/jvm/src/remoteTest/groovy/org/asciidoctor/gradle/remote/internal/RemoteSpecification.groovy
+++ b/jvm/src/remoteTest/groovy/org/asciidoctor/gradle/remote/internal/RemoteSpecification.groovy
@@ -107,7 +107,7 @@ in a subdirectory
                 executorLogLevel: ExecutorLogLevel.DEBUG,
                 failureLevel: failureLevel,
                 requires: requires,
-                gemPath: (altOptions ? gemDir.absolutePath : '')
+//                gemPath: (altOptions ? gemDir.absolutePath : '')
         )
     }
 }
diff --git a/jvm/src/test/groovy/org/asciidoctor/gradle/internal/ExecutorConfigurationSpec.groovy b/jvm/src/test/groovy/org/asciidoctor/gradle/internal/ExecutorConfigurationSpec.groovy
index 657850299..bbe343191 100644
--- a/jvm/src/test/groovy/org/asciidoctor/gradle/internal/ExecutorConfigurationSpec.groovy
+++ b/jvm/src/test/groovy/org/asciidoctor/gradle/internal/ExecutorConfigurationSpec.groovy
@@ -32,7 +32,6 @@ class ExecutorConfigurationSpec extends Specification {
             sourceTree: [fake] as Set,
             fatalMessagePatterns: [~/./],
             backendName: 'backend',
-            gemPath : 'gem:path',
             logDocuments: true,
             copyResources: true,
             legacyAttributes: true,
diff --git a/jvm/src/test/groovy/org/asciidoctor/gradle/jvm/AsciidoctorTaskSpec.groovy b/jvm/src/test/groovy/org/asciidoctor/gradle/jvm/AsciidoctorTaskSpec.groovy
index 4aadb289e..8aebb614a 100755
--- a/jvm/src/test/groovy/org/asciidoctor/gradle/jvm/AsciidoctorTaskSpec.groovy
+++ b/jvm/src/test/groovy/org/asciidoctor/gradle/jvm/AsciidoctorTaskSpec.groovy
@@ -410,47 +410,6 @@ class AsciidoctorTaskSpec extends Specification {
         !systemOut.toString().contains('deprecated')
     }
 
-    void "Allow setting of gemPath via method"() {
-        when:
-        final task = createTask {
-            asciidoctorj {
-                gemPaths project.projectDir
-            }
-        }
-
-        then:
-        !systemOut.toString().contains('deprecated')
-        task.asciidoctorj.asGemPath() == project.projectDir.absolutePath
-    }
-
-    void "When setting gemPath via assignment"() {
-        when:
-        final task = createTask {
-            asciidoctorj {
-                gemPaths = [project.projectDir]
-            }
-        }
-
-        then:
-        task.asciidoctorj.asGemPath() == project.projectDir.absolutePath
-        !systemOut.toString().contains('deprecated')
-    }
-
-    void "When setting gemPath via setGemPaths"() {
-        when:
-        project.allprojects {
-            asciidoctorj {
-                gemPaths = [project.projectDir]
-            }
-        }
-        final task = createTask {
-        }
-
-        then:
-        task.asciidoctorj.asGemPath() == project.projectDir.absolutePath
-        !systemOut.toString().contains('deprecated')
-    }
-
     void 'When attribute providers are registered on the task, then global ones will not be used.'() {
         when:
         final task = createTask {
@@ -465,10 +424,6 @@ class AsciidoctorTaskSpec extends Specification {
         task.attributeProviders != project.extensions.getByType(AsciidoctorJExtension).attributeProviders
     }
 
-    void 'Set processMode via string'() {
-        c
-    }
-
     void 'Asciidoctor task with non-default name has different source directory'() {
         when:
         AsciidoctorTask task = project.tasks.create(name: 'kilowatt', type: AsciidoctorTask)
diff --git a/module-versions.properties b/module-versions.properties
index 2b6483500..e8c4fdf71 100644
--- a/module-versions.properties
+++ b/module-versions.properties
@@ -4,7 +4,7 @@
 asciidoctorj=2.5.7
 asciidoctorj.groovydsl=2.0.2
 asciidoctorj.diagram=2.2.3
-asciidoctorj.pdf=2.3.4
+asciidoctorj.pdf=2.3.10
 asciidoctorj.epub=1.5.1
 asciidoctorj.leanpub=2.0-alpha.2
 
diff --git a/settings.gradle b/settings.gradle
index e3a175964..5092d0b05 100644
--- a/settings.gradle
+++ b/settings.gradle
@@ -19,17 +19,19 @@ include 'asciidoctoreditorconfig'
     project(":${it}").name = "asciidoctor-gradle-${it}"
 }
 
+[ 'pdf','epub'/*,  'leanpub' */ ].each {
+    include "jvm-${it}"
+    project(":jvm-${it}").name = "asciidoctor-gradle-jvm-${it}"
+}
+
 ////[  'slides-export' ].each {
 ////    include it
 ////    project(":${it}").name = "asciidoctor-gradle-${it}"
 ////}
 //
-//[ 'epub', 'pdf', 'leanpub'  ].each {
-//    include "jvm-${it}"
-//    project(":jvm-${it}").name = "asciidoctor-gradle-jvm-${it}"
-//}
-//
-//[ 'gems' /*, 'slides'*/ ].each {
-//    include it
-//    project(":${it}").name = "asciidoctor-gradle-jvm-${it}"
-//}
+
+
+[ 'gems' /*, 'slides'*/ ].each {
+    include it
+    project(":${it}").name = "asciidoctor-gradle-jvm-${it}"
+}
diff --git a/testfixtures/jvm/src/main/groovy/org/asciidoctor/gradle/testfixtures/CachingTestFixture.groovy b/testfixtures/jvm/src/main/groovy/org/asciidoctor/gradle/testfixtures/CachingTestFixture.groovy
index 1be37704e..74d9604b9 100644
--- a/testfixtures/jvm/src/main/groovy/org/asciidoctor/gradle/testfixtures/CachingTestFixture.groovy
+++ b/testfixtures/jvm/src/main/groovy/org/asciidoctor/gradle/testfixtures/CachingTestFixture.groovy
@@ -61,7 +61,7 @@ trait CachingTestFixture {
                 dslType,
                 projectDir, ['clean', task, '--build-cache', '-s'] + buildScanArguments
         ).build()
-        assert result.task(task).outcome == outcome
+        assert result.task(task)?.outcome == outcome
     }
 
     void assertTaskRunsWithOutcome(String task, TaskOutcome outcome) {
diff --git a/testfixtures/jvm/src/main/groovy/org/asciidoctor/gradle/testfixtures/FunctionalTestFixture.groovy b/testfixtures/jvm/src/main/groovy/org/asciidoctor/gradle/testfixtures/FunctionalTestFixture.groovy
index 29037d631..03eb23963 100644
--- a/testfixtures/jvm/src/main/groovy/org/asciidoctor/gradle/testfixtures/FunctionalTestFixture.groovy
+++ b/testfixtures/jvm/src/main/groovy/org/asciidoctor/gradle/testfixtures/FunctionalTestFixture.groovy
@@ -27,6 +27,7 @@ import static org.asciidoctor.gradle.testfixtures.FunctionalTestSetup.getOffline
  * Apply this trait to integration tests.
  */
 @CompileStatic
+@SuppressWarnings('DuplicateStringLiteral')
 trait FunctionalTestFixture {
 
     public static final String TEST_REPO_DIR = System.getProperty(
@@ -34,8 +35,6 @@ trait FunctionalTestFixture {
             './testfixtures/offline-repo/build/repo'
     )
 
-    abstract File getTestProjectDir()
-
     File getProjectDir() { new File(testProjectDir, 'test-project') }
 
     File getBuildFile() { new File(projectDir, 'build.gradle') }
@@ -66,4 +65,43 @@ trait FunctionalTestFixture {
         FunctionalTestSetup.getGradleRunner(KOTLIN_DSL, projectDir, taskNames)
     }
 
+    File writeGroovyBuildFile(Collection<String> plugins, String extraContent) {
+        buildFile.withWriter { w ->
+            w.println 'plugins {'
+            plugins.each { p ->
+                w.println "  id '${p}'"
+            }
+            w.println '}'
+            w.println()
+            w.println(offlineRepositories)
+            w.println()
+            w.println(extraContent)
+        }
+        buildFile
+    }
+
+    File writeGroovyBuildFile(String plugin, String extraContent) {
+        writeGroovyBuildFile([plugin], extraContent)
+    }
+
+    File writeKotlinBuildFile(Collection<String> plugins, String extraContent) {
+        buildFileKts.withWriter { w ->
+            w.println 'plugins {'
+            plugins.each { p ->
+                w.println "  id (\"${p}\")"
+            }
+            w.println '}'
+            w.println()
+            w.println(getOfflineRepositories(KOTLIN_DSL))
+            w.println()
+            w.println(extraContent)
+        }
+        buildFileKts
+    }
+
+    File writeKotlinBuildFile(String plugin, String extraContent) {
+        writeKotlinBuildFile([plugin], extraContent)
+    }
+
+    abstract File getTestProjectDir()
 }
\ No newline at end of file
diff --git a/testfixtures/jvm/src/main/groovy/org/asciidoctor/gradle/testfixtures/GradleTestVersions.groovy b/testfixtures/jvm/src/main/groovy/org/asciidoctor/gradle/testfixtures/GradleTestVersions.groovy
index 199fa14b4..7cfe220c8 100644
--- a/testfixtures/jvm/src/main/groovy/org/asciidoctor/gradle/testfixtures/GradleTestVersions.groovy
+++ b/testfixtures/jvm/src/main/groovy/org/asciidoctor/gradle/testfixtures/GradleTestVersions.groovy
@@ -19,7 +19,7 @@ import groovy.transform.CompileStatic
 import org.gradle.util.GradleVersion
 
 /**
- * Verions of Gradle that can be used for testing with TestKit.
+ * Verisons of Gradle that can be used for testing with TestKit.
  *
  * @author Schalk W. Cronjé
  *
@@ -27,8 +27,8 @@ import org.gradle.util.GradleVersion
  */
 @CompileStatic
 class GradleTestVersions {
-    public final static String MIN_VERSION = '6.0.1'
-    public final static String MAX_VERSION = '7.6'
+    public final static String MIN_VERSION = '7.0.1'
+    public final static String MAX_VERSION = '8.5'
 
     static String latestMinimumOrThis(final String ver) {
         [GradleVersion.version(MIN_VERSION), GradleVersion.version(ver)].max().version