diff --git a/plugins/tester/src/main/java/com.github.forax.pro.plugin.tester/com/github/forax/pro/plugin/tester/TesterPlugin.java b/plugins/tester/src/main/java/com.github.forax.pro.plugin.tester/com/github/forax/pro/plugin/tester/TesterPlugin.java
index bcf5598..d93b05b 100644
--- a/plugins/tester/src/main/java/com.github.forax.pro.plugin.tester/com/github/forax/pro/plugin/tester/TesterPlugin.java
+++ b/plugins/tester/src/main/java/com.github.forax.pro.plugin.tester/com/github/forax/pro/plugin/tester/TesterPlugin.java
@@ -3,6 +3,7 @@
 import static com.github.forax.pro.api.MutableConfig.derive;
 
 import java.io.IOException;
+import java.lang.module.ModuleDescriptor;
 import java.lang.module.ModuleFinder;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.UndeclaredThrowableException;
@@ -88,9 +89,11 @@ private int execute(TesterConf tester, Path testPath) throws IOException {
     var loader = createTestClassLoader(tester, testPath, moduleName);
     
     var testConfClass = load(loader, TestConf.class);
-    var testConf = create(testConfClass, new Class<?>[] { java.lang.module.ModuleDescriptor.class, boolean.class}, moduleDescriptor, tester.parallel());
+    var testConfTypes = new Class<?>[] {ModuleDescriptor.class, boolean.class};
+    var testConf = create(testConfClass, testConfTypes, moduleDescriptor, tester.parallel());
     var runnerClass = load(loader, TesterRunner.class);
-    var runner = (IntSupplier) create(runnerClass, new Class<?>[] { testConfClass }, testConf);
+    var runnerTypes = new Class<?>[] {testConfClass};
+    var runner = (IntSupplier) create(runnerClass, runnerTypes, testConf);
      
     try {
       var future = executor.submit(runner::getAsInt);
diff --git a/plugins/tester/src/main/java/com.github.forax.pro.plugin.tester/com/github/forax/pro/plugin/tester/TesterRunner.java b/plugins/tester/src/main/java/com.github.forax.pro.plugin.tester/com/github/forax/pro/plugin/tester/TesterRunner.java
index 03b68ac..764695a 100644
--- a/plugins/tester/src/main/java/com.github.forax.pro.plugin.tester/com/github/forax/pro/plugin/tester/TesterRunner.java
+++ b/plugins/tester/src/main/java/com.github.forax.pro.plugin.tester/com/github/forax/pro/plugin/tester/TesterRunner.java
@@ -34,15 +34,16 @@ private static int launchJUnitPlatform(TestConf testConf) {
     var moduleName = testConf.moduleName();
     var moduleNameAndVersion = testConf.moduleNameAndVersion();
     var parallel = testConf.parallel();
-    
+
     var builder = LauncherDiscoveryRequestBuilder.request();
     builder.selectors(selectModule(moduleName));
-    builder.configurationParameter("junit.jupiter.execution.parallel.enabled", "" + parallel);
+    builder.configurationParameter("junit.jupiter.execution.parallel.enabled", Boolean.toString(parallel));
 
-    var startTimeMillis = System.currentTimeMillis();
+    var launcher = LauncherFactory.create();
     var launcherDiscoveryRequest = builder.build();
     var summaryGeneratingListener = new SummaryGeneratingListener();
-    LauncherFactory.create().execute(launcherDiscoveryRequest, summaryGeneratingListener);
+    var startTimeMillis = System.currentTimeMillis();
+    launcher.execute(launcherDiscoveryRequest, summaryGeneratingListener);
     var duration = System.currentTimeMillis() - startTimeMillis;
     var summary = summaryGeneratingListener.getSummary();
     int failures = (int) summary.getTestsFailedCount();