diff --git a/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/subtargets/KotlinBrowserJs.kt b/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/subtargets/KotlinBrowserJs.kt
index 69aca00f25e..a6f9a6f4af0 100644
--- a/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/subtargets/KotlinBrowserJs.kt
+++ b/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/subtargets/KotlinBrowserJs.kt
@@ -16,6 +16,7 @@ import org.jetbrains.kotlin.gradle.targets.js.nodejs.NodeJsRootPlugin
 import org.jetbrains.kotlin.gradle.targets.js.testing.KotlinJsTest
 import org.jetbrains.kotlin.gradle.targets.js.webpack.KotlinWebpack
 import org.jetbrains.kotlin.gradle.targets.js.webpack.KotlinWebpackConfig
+import org.jetbrains.kotlin.gradle.targets.js.webpack.KotlinWebpackConfig.Mode
 import org.jetbrains.kotlin.gradle.tasks.registerTask
 import org.jetbrains.kotlin.gradle.utils.lowerCamelCaseName
 import javax.inject.Inject
@@ -66,6 +67,7 @@ open class KotlinBrowserJs @Inject constructor(target: KotlinJsTarget) :
                 target.project.tasks.getByName(compilation.processResourcesTaskName)
             )
 
+            it.mode = Mode.DEVELOPMENT
             it.bin = "webpack-dev-server/bin/webpack-dev-server.js"
             it.compilation = compilation
             it.description = "start webpack dev server"
@@ -100,6 +102,11 @@ open class KotlinBrowserJs @Inject constructor(target: KotlinJsTarget) :
                     compileKotlinTask
                 )
 
+                it.mode = when (buildVariant.kind) {
+                    BuildVariantKind.RELEASE -> Mode.PRODUCTION
+                    BuildVariantKind.DEBUG -> Mode.DEVELOPMENT
+                }
+
                 it.compilation = compilation
                 it.description = "build webpack bundle"
 
diff --git a/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/webpack/KotlinWebpack.kt b/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/webpack/KotlinWebpack.kt
index e5318d92f5f..ec90632ccc3 100644
--- a/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/webpack/KotlinWebpack.kt
+++ b/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/webpack/KotlinWebpack.kt
@@ -20,6 +20,7 @@ import org.jetbrains.kotlin.gradle.targets.js.RequiredKotlinJsDependency
 import org.jetbrains.kotlin.gradle.targets.js.nodejs.NodeJsRootPlugin
 import org.jetbrains.kotlin.gradle.targets.js.npm.RequiresNpmDependencies
 import org.jetbrains.kotlin.gradle.targets.js.npm.npmProject
+import org.jetbrains.kotlin.gradle.targets.js.webpack.KotlinWebpackConfig.Mode
 import org.jetbrains.kotlin.gradle.testing.internal.reportsDir
 import org.jetbrains.kotlin.gradle.utils.injected
 import java.io.File
@@ -47,6 +48,9 @@ open class KotlinWebpack : DefaultTask(), RequiresNpmDependencies {
             target.project.path + "@" + target.name + ":" + it.compilationName
         }
 
+    @Input
+    var mode: Mode = Mode.PRODUCTION
+
     @get:PathSensitive(PathSensitivity.ABSOLUTE)
     @get:InputFile
     val entry: File
@@ -110,6 +114,7 @@ open class KotlinWebpack : DefaultTask(), RequiresNpmDependencies {
         execHandleFactory,
         bin,
         KotlinWebpackConfig(
+            mode = mode,
             entry = entry,
             reportEvaluatedConfigFile = if (saveEvaluatedConfigFile) evaluatedConfigFile else null,
             outputPath = destinationDirectory,