diff --git a/compiler/backend/src/org/jetbrains/jet/compiler/CompileEnvironment.java b/compiler/backend/src/org/jetbrains/jet/compiler/CompileEnvironment.java
index 1987193c89a..ae74afa756c 100644
--- a/compiler/backend/src/org/jetbrains/jet/compiler/CompileEnvironment.java
+++ b/compiler/backend/src/org/jetbrains/jet/compiler/CompileEnvironment.java
@@ -7,6 +7,9 @@ import com.intellij.openapi.util.io.FileUtil;
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.util.Function;
 import com.intellij.util.Processor;
+import jet.ExtensionFunction0;
+import jet.ExtensionFunction10;
+import jet.Function1;
 import jet.modules.IModuleBuilder;
 import jet.modules.IModuleSetBuilder;
 import org.jetbrains.annotations.Nullable;
@@ -18,6 +21,7 @@ import org.jetbrains.jet.lang.psi.JetPsiUtil;
 import org.jetbrains.jet.plugin.JetMainDetector;
 
 import java.io.*;
+import java.lang.reflect.Field;
 import java.lang.reflect.Method;
 import java.net.URL;
 import java.net.URLClassLoader;
@@ -198,17 +202,19 @@ public class CompileEnvironment {
             final IModuleSetBuilder moduleSetBuilder = (IModuleSetBuilder) moduleSetBuilderClass.newInstance();
 
             Class namespaceClass = loader.loadClass("namespace");
-            final Method[] methods = namespaceClass.getMethods();
+            final Field[] fields = namespaceClass.getDeclaredFields();
             boolean modulesDefined = false;
-            for (Method method : methods) {
-                if (method.getName().equals("defineModules")) {
-                    method.invoke(null, moduleSetBuilder);
+            for (Field field : fields) {
+                if (field.getName().equals("modules")) {
+                    field.setAccessible(true);
+                    ExtensionFunction0 defineMudules = (ExtensionFunction0) field.get(null);
+                    defineMudules.invoke(moduleSetBuilder);
                     modulesDefined = true;
                     break;
                 }
             }
             if (!modulesDefined) {
-                throw new CompileEnvironmentException("Module script " + moduleFile + " must define a defineModules() method");
+                throw new CompileEnvironmentException("Module script " + moduleFile + " must define a modules() property");
             }
             return moduleSetBuilder;
         } catch (Exception e) {
diff --git a/compiler/testData/compiler/smoke/Smoke.kts b/compiler/testData/compiler/smoke/Smoke.kts
index 6cdcff74a64..d9429cd1b65 100644
--- a/compiler/testData/compiler/smoke/Smoke.kts
+++ b/compiler/testData/compiler/smoke/Smoke.kts
@@ -1,8 +1,6 @@
-import kotlin.modules.ModuleSetBuilder
+import kotlin.modules.*
 
-fun ModuleSetBuilder.defineModules() {
-    module("smoke") {
-        source files "Smoke.kt"
-        jar name System.getProperty("java.io.tmpdir") + "/smoke.jar"
-    }
+val modules = module("smoke") {
+    source files "Smoke.kt"
+    jar name System.getProperty("java.io.tmpdir") + "/smoke.jar"
 }
diff --git a/stdlib/ktSrc/ModuleBuilder.kt b/stdlib/ktSrc/modules/ModuleBuilder.kt
similarity index 87%
rename from stdlib/ktSrc/ModuleBuilder.kt
rename to stdlib/ktSrc/modules/ModuleBuilder.kt
index cf1ffcdd896..59784ab0521 100644
--- a/stdlib/ktSrc/ModuleBuilder.kt
+++ b/stdlib/ktSrc/modules/ModuleBuilder.kt
@@ -5,8 +5,14 @@ package modules {
 import java.util.*
 import jet.modules.*
 
+fun moduleSet(description: ModuleSetBuilder.() -> Unit) = description
+
+fun module(name: String, description: ModuleBuilder.() -> Unit) = moduleSet {
+    module(name, description)
+}
+
 class ModuleSetBuilder(): IModuleSetBuilder {
-    val modules: ArrayList<IModuleBuilder?> = ArrayList<IModuleBuilder?>()
+    private val modules = ArrayList<IModuleBuilder?>()
 
     fun module(name: String, callback:  ModuleBuilder.() -> Unit) {
         val builder = ModuleBuilder(name)