diff --git a/.github/workflows/cibuild.yml b/.github/workflows/cibuild.yml
index 41bbce0e12..d0c808584a 100644
--- a/.github/workflows/cibuild.yml
+++ b/.github/workflows/cibuild.yml
@@ -42,6 +42,7 @@ jobs:
         java:
         - '8'
         - '11'
+        - '18'
         runner:
         - 'xvfb-run --auto-servernum {0}'
         include:
diff --git a/.github/workflows/rebuild.yml b/.github/workflows/rebuild.yml
index b1bb641b64..4dcdac2456 100644
--- a/.github/workflows/rebuild.yml
+++ b/.github/workflows/rebuild.yml
@@ -73,7 +73,7 @@ jobs:
         - 'ubuntu-latest'
         java:
         - '8'
-        - '17'
+        - '18'
         runner:
         - 'xvfb-run --auto-servernum {0}'
     name: Rebuild JDK${{ matrix.java }} ${{ matrix.os }}
diff --git a/gradle-plugins/README.md b/gradle-plugins/README.md
index a4f0427bf9..ee9dfb08b2 100644
--- a/gradle-plugins/README.md
+++ b/gradle-plugins/README.md
@@ -7,7 +7,8 @@ A Bnd Workspace build uses the information specified in the Bnd Workspace's `cnf
 The [`biz.aQute.bnd.gradle`][2] jar contains the Bnd Gradle Plugins.
 These plugins requires at least Gradle 6.7 for Java 8 to Java 15,
 at least Gradle 7.0 for Java 16,
-and at least Gradle 7.3 for Java 17.
+at least Gradle 7.3 for Java 17,
+and at least Gradle 7.5 for Java 18.
 
 This README represents the capabilities and features of the Bnd Gradle Plugins in the branch containing this README.
 So for the `master` branch, this will be the [latest development SNAPSHOT build](#using-the-latest-development-snapshot-build-of-the-bnd-gradle-plugins).
@@ -138,7 +139,7 @@ The FileCollection object to use as the classpath for the Bnd builder.
 The default value is _${project.sourceSets.main.compileClasspath}_.
 You will only need to specify this property if you want to specify additional classpath elements or replace the classpath.
 
-### properties 
+### properties
 
 Properties that are available for evaluation of the Bnd instructions.
 The default is the properties of the Gradle task and project objects.
@@ -382,7 +383,7 @@ This property must not be used for and is ignored in Bnd Workspace builds.
 If `true` failure reports will include optional requirements.
 The default is `true`.
 
-### properties 
+### properties
 
 Properties that are available for evaluation of the Bnd instructions.
 The default is the properties of the Gradle task and project objects.
@@ -436,7 +437,7 @@ The collection of files to use for locating bundles during the bndrun export.
 The default is _${project.sourceSets.main.runtimeClasspath}_ plus _${project.configurations.archives.artifacts.files}_.
 This property must not be used for and is ignored in Bnd Workspace builds.
 
-### properties 
+### properties
 
 Properties that are available for evaluation of the Bnd instructions.
 The default is the properties of the Gradle task and project objects.
@@ -496,9 +497,9 @@ The default is _${project.java.testResultsDir}/${task.name}_.
 ### javaLauncher
 
 Specify the default java executable to be used for execution.
-This java launcher is used if the bndrun does not specify the `java` property or specifies it with the default value `java`. 
+This java launcher is used if the bndrun does not specify the `java` property or specifies it with the default value `java`.
 
-### properties 
+### properties
 
 Properties that are available for evaluation of the Bnd instructions.
 The default is the properties of the Gradle task and project objects.
@@ -609,9 +610,9 @@ This property must not be used for and is ignored in Bnd Workspace builds.
 ### javaLauncher
 
 Specify the default java executable to be used for execution.
-This java launcher is used if the bndrun does not specify the `java` property or specifies it with the default value `java`. 
+This java launcher is used if the bndrun does not specify the `java` property or specifies it with the default value `java`.
 
-### properties 
+### properties
 
 Properties that are available for evaluation of the Bnd instructions.
 The default is the properties of the Gradle task and project objects.
diff --git a/gradle-plugins/biz.aQute.bnd.gradle/src/main/java/aQute/bnd/gradle/BndBuilderPlugin.java b/gradle-plugins/biz.aQute.bnd.gradle/src/main/java/aQute/bnd/gradle/BndBuilderPlugin.java
index 2100abd2b3..5f33d02f80 100644
--- a/gradle-plugins/biz.aQute.bnd.gradle/src/main/java/aQute/bnd/gradle/BndBuilderPlugin.java
+++ b/gradle-plugins/biz.aQute.bnd.gradle/src/main/java/aQute/bnd/gradle/BndBuilderPlugin.java
@@ -46,6 +46,11 @@ public class BndBuilderPlugin implements Plugin<Project> {
 	 */
 	public static final String	PLUGINID		= "biz.aQute.bnd.builder";
 
+	/**
+	 * Default public constructor.
+	 */
+	public BndBuilderPlugin() {}
+
 	/**
 	 * Apply the {@code biz.aQute.bnd.builder} plugin to the specified project.
 	 */
diff --git a/gradle-plugins/biz.aQute.bnd.gradle/src/main/java/aQute/bnd/gradle/BndPlugin.java b/gradle-plugins/biz.aQute.bnd.gradle/src/main/java/aQute/bnd/gradle/BndPlugin.java
index acdc1940cd..9e38f1ee7b 100644
--- a/gradle-plugins/biz.aQute.bnd.gradle/src/main/java/aQute/bnd/gradle/BndPlugin.java
+++ b/gradle-plugins/biz.aQute.bnd.gradle/src/main/java/aQute/bnd/gradle/BndPlugin.java
@@ -104,6 +104,11 @@ public class BndPlugin implements Plugin<Project> {
 	private ObjectFactory					objects;
 	private aQute.bnd.build.Project			bndProject;
 
+	/**
+	 * Default public constructor.
+	 */
+	public BndPlugin() {}
+
 	/**
 	 * Apply the {@code biz.aQute.bnd} plugin to the specified project.
 	 */
diff --git a/gradle-plugins/biz.aQute.bnd.gradle/src/main/java/aQute/bnd/gradle/BndWorkspacePlugin.java b/gradle-plugins/biz.aQute.bnd.gradle/src/main/java/aQute/bnd/gradle/BndWorkspacePlugin.java
index 97f6d451cf..ed7874aedb 100644
--- a/gradle-plugins/biz.aQute.bnd.gradle/src/main/java/aQute/bnd/gradle/BndWorkspacePlugin.java
+++ b/gradle-plugins/biz.aQute.bnd.gradle/src/main/java/aQute/bnd/gradle/BndWorkspacePlugin.java
@@ -50,6 +50,11 @@ public class BndWorkspacePlugin implements Plugin<Object> {
 	private static final Pattern		TASKNAME_SPLITTER	= Pattern.compile(":");
 	private static final Set<String>	SPECIAL_FOLDERS		= Sets.of("buildSrc", "gradle");
 
+	/**
+	 * Default public constructor.
+	 */
+	public BndWorkspacePlugin() {}
+
 	/**
 	 * Apply the {@code biz.aQute.bnd.workspace} plugin.
 	 */
diff --git a/gradle-plugins/biz.aQute.bnd.gradle/src/test/groovy/aQute/bnd/gradle/TestHelper.groovy b/gradle-plugins/biz.aQute.bnd.gradle/src/test/groovy/aQute/bnd/gradle/TestHelper.groovy
index 7d5e0db30d..d894faa5db 100644
--- a/gradle-plugins/biz.aQute.bnd.gradle/src/test/groovy/aQute/bnd/gradle/TestHelper.groovy
+++ b/gradle-plugins/biz.aQute.bnd.gradle/src/test/groovy/aQute/bnd/gradle/TestHelper.groovy
@@ -39,6 +39,9 @@ class TestHelper {
 	}
 
 	private static String gradleVersion() {
+		if (JavaVersion.current().isCompatibleWith(JavaVersion.VERSION_18)) {
+			return "7.5"
+		}
 		if (JavaVersion.current().isCompatibleWith(JavaVersion.VERSION_17)) {
 			return "7.3.2"
 		}
diff --git a/gradle/wrapper/gradle-wrapper.jar b/gradle/wrapper/gradle-wrapper.jar
index 41d9927a4d..249e5832f0 100644
Binary files a/gradle/wrapper/gradle-wrapper.jar and b/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index aa991fceae..8049c684f0 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-7.4.2-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.5-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
diff --git a/gradlew b/gradlew
index 1b6c787337..a69d9cb6c2 100755
--- a/gradlew
+++ b/gradlew
@@ -205,6 +205,12 @@ set -- \
         org.gradle.wrapper.GradleWrapperMain \
         "$@"
 
+# Stop when "xargs" is not available.
+if ! command -v xargs >/dev/null 2>&1
+then
+    die "xargs is not available"
+fi
+
 # Use "xargs" to parse quoted args.
 #
 # With -n1 it outputs one arg per line, with the quotes and backslashes removed.
diff --git a/gradlew.bat b/gradlew.bat
index ac1b06f938..53a6b238d4 100644
--- a/gradlew.bat
+++ b/gradlew.bat
@@ -14,7 +14,7 @@
 @rem limitations under the License.
 @rem
 
-@if "%DEBUG%" == "" @echo off
+@if "%DEBUG%"=="" @echo off
 @rem ##########################################################################
 @rem
 @rem  Gradle startup script for Windows
@@ -25,7 +25,7 @@
 if "%OS%"=="Windows_NT" setlocal
 
 set DIRNAME=%~dp0
-if "%DIRNAME%" == "" set DIRNAME=.
+if "%DIRNAME%"=="" set DIRNAME=.
 set APP_BASE_NAME=%~n0
 set APP_HOME=%DIRNAME%
 
@@ -40,7 +40,7 @@ if defined JAVA_HOME goto findJavaFromJavaHome
 
 set JAVA_EXE=java.exe
 %JAVA_EXE% -version >NUL 2>&1
-if "%ERRORLEVEL%" == "0" goto execute
+if %ERRORLEVEL% equ 0 goto execute
 
 echo.
 echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
@@ -75,13 +75,15 @@ set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
 
 :end
 @rem End local scope for the variables with windows NT shell
-if "%ERRORLEVEL%"=="0" goto mainEnd
+if %ERRORLEVEL% equ 0 goto mainEnd
 
 :fail
 rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
 rem the _cmd.exe /c_ return code!
-if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
-exit /b 1
+set EXIT_CODE=%ERRORLEVEL%
+if %EXIT_CODE% equ 0 set EXIT_CODE=1
+if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
+exit /b %EXIT_CODE%
 
 :mainEnd
 if "%OS%"=="Windows_NT" endlocal