diff --git a/.github/workflows/bld.yml b/.github/workflows/bld.yml
index 436605a..8fafac9 100644
--- a/.github/workflows/bld.yml
+++ b/.github/workflows/bld.yml
@@ -12,7 +12,7 @@ jobs:
     strategy:
       matrix:
         java-version: [17, 21, 23]
-        kotlin-version: [1.9.24, 2.0.21, 2.1.0]
+        kotlin-version: [1.9.24, 2.0.21]
 
     steps:
       - name: Checkout source repository
diff --git a/examples/lib/bld/bld-wrapper.properties b/examples/lib/bld/bld-wrapper.properties
index 686fe3c..28c5833 100644
--- a/examples/lib/bld/bld-wrapper.properties
+++ b/examples/lib/bld/bld-wrapper.properties
@@ -1,7 +1,7 @@
 bld.downloadExtensionJavadoc=false
 bld.downloadExtensionSources=true
 bld.downloadLocation=
-bld.extension-kotlin=com.uwyn.rife2:bld-kotlin:1.0.3
+bld.extension-kotlin=com.uwyn.rife2:bld-kotlin:1.0.2
 bld.repositories=MAVEN_LOCAL,MAVEN_CENTRAL,RIFE2_SNAPSHOTS,RIFE2_RELEASES
 bld.sourceDirectories=
 bld.version=2.1.0
diff --git a/examples/src/bld/java/com/example/ExampleBuild.java b/examples/src/bld/java/com/example/ExampleBuild.java
index 83948b0..993767b 100644
--- a/examples/src/bld/java/com/example/ExampleBuild.java
+++ b/examples/src/bld/java/com/example/ExampleBuild.java
@@ -28,7 +28,7 @@ public class ExampleBuild extends Project {
 
         repositories = List.of(MAVEN_LOCAL, MAVEN_CENTRAL, RIFE2_RELEASES);
 
-        final var kotlin = version(2, 1, 0);
+        final var kotlin = version(2, 0, 21);
         scope(compile)
                 .include(dependency("org.jetbrains.kotlin", "kotlin-stdlib", kotlin));
         scope(test)
@@ -58,11 +58,14 @@ public class ExampleBuild extends Project {
     @Override
     public void compile() throws Exception {
         // The source code located in src/main/kotlin and src/test/kotlin will be compiled
-        var op = new CompileKotlinOperation()
+        new CompileKotlinOperation()
+                .fromProject(this)
 //                .kotlinHome("path/to/kotlin")
 //                .kotlinc("path/to/kotlinc")
-                .fromProject(this);
-        op.compileOptions().verbose(true);
-        op.execute();
+                .execute();
+
+//        var op = new CompileKotlinOperation().fromProject(this);
+//        op.compileOptions().verbose(true);
+//        op.execute();
     }
 }
diff --git a/scripts/checkcliargs.sh b/scripts/checkcliargs.sh
index 30c8537..ef320da 100755
--- a/scripts/checkcliargs.sh
+++ b/scripts/checkcliargs.sh
@@ -4,7 +4,7 @@ new=/tmp/checkcliargs-new
 old=/tmp/checkcliargs-old
 
 kotlinc -h 2>$new
-~/.sdkman/candidates/kotlin/2.1.0/bin/kotlinc -h 2>$old
+~/.sdkman/candidates/kotlin/2.0.0/bin/kotlinc -h 2>$old
 
 code --diff --wait $old $new
 
diff --git a/src/bld/java/rife/bld/extension/CompileKotlinOperationBuild.java b/src/bld/java/rife/bld/extension/CompileKotlinOperationBuild.java
index 157d16e..6a84505 100644
--- a/src/bld/java/rife/bld/extension/CompileKotlinOperationBuild.java
+++ b/src/bld/java/rife/bld/extension/CompileKotlinOperationBuild.java
@@ -33,7 +33,7 @@ public class CompileKotlinOperationBuild extends Project {
     public CompileKotlinOperationBuild() {
         pkg = "rife.bld.extension";
         name = "bld-kotlin";
-        version = version(1, 0, 3);
+        version = version(1, 0, 3, "SNAPSHOT");
 
         javaRelease = 17;
 
diff --git a/src/main/java/rife/bld/extension/CompileKotlinOperation.java b/src/main/java/rife/bld/extension/CompileKotlinOperation.java
index f2c0ecb..8143f5d 100644
--- a/src/main/java/rife/bld/extension/CompileKotlinOperation.java
+++ b/src/main/java/rife/bld/extension/CompileKotlinOperation.java
@@ -406,11 +406,9 @@ public class CompileKotlinOperation extends AbstractOperation<CompileKotlinOpera
     public CompileKotlinOperation fromProject(BaseProject project) {
         project_ = project;
 
-        if (kotlinHome_ == null) {
-            var env = System.getenv("KOTLIN_HOME");
-            if (env != null) {
-                kotlinHome_ = new File(env);
-            }
+        var env = System.getenv("KOTLIN_HOME");
+        if (env != null) {
+            kotlinHome_ = new File(env);
         }
 
         workDir_ = new File(project.workDirectory().getAbsolutePath());
diff --git a/src/main/java/rife/bld/extension/kotlin/CompileOptions.java b/src/main/java/rife/bld/extension/kotlin/CompileOptions.java
index a108bdf..002a2e5 100644
--- a/src/main/java/rife/bld/extension/kotlin/CompileOptions.java
+++ b/src/main/java/rife/bld/extension/kotlin/CompileOptions.java
@@ -60,7 +60,6 @@ public class CompileOptions {
     private boolean progressive_;
     private boolean verbose_;
     private boolean wError_;
-    private boolean wExtra_;
 
     /**
      * Specify advanced compiler options.
@@ -375,16 +374,11 @@ public class CompileOptions {
             args.add("-verbose");
         }
 
-        // Wwrror
+        // Werror
         if (wError_) {
             args.add("-Werror");
         }
 
-        // Wextra
-        if (wExtra_) {
-            args.add("-Wextra");
-        }
-
         // advanced option (X)
         if (!advancedOptions_.isEmpty()) {
             advancedOptions_.forEach(it -> args.add("-X" + it));
@@ -603,15 +597,6 @@ public class CompileOptions {
         return wError_;
     }
 
-    /**
-     * Indicates whether additional declaration, expression, and type compiler checks emit warnings.
-     *
-     * @return {@code true} or {@code false}
-     */
-    public boolean isWExtra() {
-        return wExtra_;
-    }
-
     /**
      * Generate metadata for Java 1.8 reflection on method parameters.
      *
@@ -1086,15 +1071,4 @@ public class CompileOptions {
         wError_ = wError;
         return this;
     }
-
-    /**
-     * Enable additional declaration, expression, and type compiler checks that emit warnings if {@code true}.
-     *
-     * @param wExtra {@code true} or {@code false}
-     * @return this operation instance
-     */
-    public CompileOptions wExtra(boolean wExtra) {
-        wExtra_ = wExtra;
-        return this;
-    }
 }
diff --git a/src/test/java/rife/bld/extension/kotlin/CompileOptionsTest.java b/src/test/java/rife/bld/extension/kotlin/CompileOptionsTest.java
index 3bc9e25..129ab44 100644
--- a/src/test/java/rife/bld/extension/kotlin/CompileOptionsTest.java
+++ b/src/test/java/rife/bld/extension/kotlin/CompileOptionsTest.java
@@ -71,8 +71,7 @@ class CompileOptionsTest {
                 .progressive(true)
                 .scriptTemplates("name", "name2")
                 .verbose(true)
-                .wError(true)
-                .wExtra(true);
+                .wError(true);
 
         var matches = List.of(
                 "-api-version", "11",
@@ -98,8 +97,7 @@ class CompileOptionsTest {
                 "-progressive",
                 "-script-templates", "name,name2",
                 "-verbose",
-                "-Werror",
-                "-Wextra");
+                "-Werror");
 
         var args = new ArrayList<List<String>>();
         args.add(options.args());
@@ -236,8 +234,7 @@ class CompileOptionsTest {
                 .progressive(true)
                 .scriptTemplates("template")
                 .verbose(true)
-                .wError(true)
-                .wExtra(true);
+                .wError(true);
 
         try (var softly = new AutoCloseableSoftAssertions()) {
             for (var p : args) {
@@ -343,8 +340,7 @@ class CompileOptionsTest {
                 .progressive(true)
                 .scriptTemplates("name", "name2")
                 .verbose(true)
-                .wError(true)
-                .wExtra(true);
+                .wError(true);
 
         try (var softly = new AutoCloseableSoftAssertions()) {
             softly.assertThat(options.advancedOptions()).containsExactly("xopt1", "xopt2");
@@ -372,7 +368,6 @@ class CompileOptionsTest {
             softly.assertThat(options.plugin()).containsExactly("id:name:value");
             softly.assertThat(options.scriptTemplates()).containsExactly("name", "name2");
             softly.assertThat(options.isWError()).isTrue();
-            softly.assertThat(options.isWExtra()).isTrue();
         }
     }
 }
diff --git a/src/test/resources/kotlinc-args.txt b/src/test/resources/kotlinc-args.txt
index e764231..b3c7f27 100644
--- a/src/test/resources/kotlinc-args.txt
+++ b/src/test/resources/kotlinc-args.txt
@@ -22,5 +22,4 @@
 -script-templates
 -verbose
 -Werror
--Wextra
 -X