diff --git a/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/testing/karma/KotlinKarma.kt b/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/testing/karma/KotlinKarma.kt
index 9d01bb1d03e..771d16973fd 100644
--- a/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/testing/karma/KotlinKarma.kt
+++ b/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/testing/karma/KotlinKarma.kt
@@ -238,6 +238,8 @@ class KotlinKarma(override val compilation: KotlinJsCompilation) : KotlinJsTestF
             val adapterJs = npmProject.dir.resolve("adapter-browser.js")
             adapterJs.printWriter().use { writer ->
                 val karmaRunner = npmProject.require("kotlin-test-js-runner/kotlin-test-karma-runner.js")
+                // It is necessary for debugger attaching (--inspect-brk analogue)
+                writer.println("debugger;")
                 writer.println("require(${karmaRunner.jsQuoted()})")
 
                 writer.println("module.exports = require(${file.jsQuoted()})")
@@ -253,6 +255,11 @@ class KotlinKarma(override val compilation: KotlinJsCompilation) : KotlinJsTestF
         nodeJsArgs: MutableList<String>,
         debug: Boolean
     ): TCServiceMessagesTestExecutionSpec {
+        if (debug) {
+            config.client.mocha.timeout = "0"
+            config.singleRun = false
+        }
+
         if (config.browsers.isEmpty()) {
             error("No browsers configured for $task")
         }
@@ -306,15 +313,16 @@ class KotlinKarma(override val compilation: KotlinJsCompilation) : KotlinJsTestF
 
         val nodeModules = listOf("karma/bin/karma")
 
+        val karmaConfigAbsolutePath = karmaConfJs.absolutePath
         val args = if (debug) {
-            config.client.mocha.timeout = "0"
-
-            //TODO need generate it
-            listOf("./debugRunner.js")
+            listOf(
+                npmProject.require("kotlin-test-js-runner/karma-debug.js"),
+                karmaConfigAbsolutePath
+            )
         } else {
             nodeJsArgs +
                     nodeModules.map { npmProject.require(it) } +
-                    listOf("start", karmaConfJs.absolutePath)
+                    listOf("start", karmaConfigAbsolutePath)
         }
 
         return object : JSServiceMessagesTestExecutionSpec(
diff --git a/libraries/tools/kotlin-test-js-runner/build.gradle.kts b/libraries/tools/kotlin-test-js-runner/build.gradle.kts
index a979f64930c..2a53d7bb2d6 100644
--- a/libraries/tools/kotlin-test-js-runner/build.gradle.kts
+++ b/libraries/tools/kotlin-test-js-runner/build.gradle.kts
@@ -53,6 +53,7 @@ tasks {
             "nodejs.ts",
             "karma.ts",
             "karma-kotlin-reporter.js",
+            "karma-debug.js",
             "mocha-kotlin-reporter.js",
             "package.json",
             "rollup.config.js",
diff --git a/libraries/tools/kotlin-test-js-runner/karma-debug.js b/libraries/tools/kotlin-test-js-runner/karma-debug.js
new file mode 100644
index 00000000000..b6991e6ee34
--- /dev/null
+++ b/libraries/tools/kotlin-test-js-runner/karma-debug.js
@@ -0,0 +1,29 @@
+/*
+ * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+const karma = require('karma');
+
+const cfg = karma.config;
+
+const karmaConfig = cfg.parseConfig(process.argv[2]);
+
+const Server = karma.Server;
+const server = new Server(karmaConfig, function (exitCode) {
+    console.log('Karma has exited with ' + exitCode);
+});
+
+server.on('browsers_ready', function () {
+    // It is unreliable decision, but we need some delay for debugger attaching
+    setTimeout(function () {
+        karma.runner.run(karmaConfig, function (exitCode) {
+            console.log('Runner has exited with ' + exitCode);
+            karma.stopper.stop(karmaConfig, function (exitCode) {
+                console.log('Stopper has exited with ' + exitCode);
+            })
+        })
+    }, 1000)
+});
+
+server.start();
\ No newline at end of file
diff --git a/libraries/tools/kotlin-test-js-runner/rollup.config.js b/libraries/tools/kotlin-test-js-runner/rollup.config.js
index a752698f878..3ad500b2e96 100644
--- a/libraries/tools/kotlin-test-js-runner/rollup.config.js
+++ b/libraries/tools/kotlin-test-js-runner/rollup.config.js
@@ -25,6 +25,13 @@ export default [
         },
         plugins: plugins()
     },
+    {
+        input: './karma-debug.js',
+        output: {
+            file: 'lib/karma-debug.js',
+            format: 'cjs'
+        }
+    },
     {
         input: './karma-kotlin-reporter.js',
         external: ['path', 'util'],
diff --git a/libraries/tools/kotlin-test-js-runner/tsconfig.json b/libraries/tools/kotlin-test-js-runner/tsconfig.json
index bb7ef503871..d704981740f 100644
--- a/libraries/tools/kotlin-test-js-runner/tsconfig.json
+++ b/libraries/tools/kotlin-test-js-runner/tsconfig.json
@@ -4,8 +4,7 @@
     "module": "ESNext",
     "strict": true,
     "sourceMap": true,
-    "allowSyntheticDefaultImports": true,
-    "inlineSourceMap": true
+    "allowSyntheticDefaultImports": true
   },
   "exclude": [
     "**/*Debug.ts"