buildscript { ext.kotlin_version = '1.1.51' repositories { google() jcenter() } dependencies { classpath 'com.android.tools.build:gradle:3.0.0' classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version" } } allprojects { repositories { google() jcenter() } } task clean(type: Delete) { delete rootProject.buildDir }