Butterknife 8.4.0 - Plugin with id 'android-apt' not found -

i keep getting error plugin id 'android-apt' not found. what's going wrong here?

plugins {     id "me.tatarka.retrolambda" version "3.2.5" }  apply plugin: 'com.android.application' apply plugin: 'android-apt'  android {     compilesdkversion 24     buildtoolsversion '23.0.3'      dexoptions {         javamaxheapsize "6g"     }      defaultconfig {         applicationid "com.yitter.android"         minsdkversion 15         targetsdkversion 24          multidexenabled true // enabling multidex support.         renderscripttargetapi 23         renderscriptsupportmodeenabled true     }      buildtypes {         release {             minifyenabled false             //runproguard false             //proguardfiles getdefaultproguardfile('proguard-android.txt'), 'proguard-rules.txt'         }     }      compileoptions {         sourcecompatibility javaversion.version_1_8         targetcompatibility javaversion.version_1_8     } }  repositories {     mavencentral()     maven { url "https://jitpack.io" } }  dependencies {     //neumob     compile 'com.neumob:neumob-android:2.3.7'      // material design navigation drawer     compile('com.mikepenz:materialdrawer:5.3.6@aar') {         transitive = true     }      // crop image     compile 'com.theartofdev.edmodo:android-image-cropper:2.2.+'      // material design font icons     compile "com.mikepenz:iconics-core:2.7.1@aar"     compile "com.android.support:appcompat-v7:24.1.1"     compile 'com.mikepenz:google-material-typeface:2.2.0.2.original@aar'     compile 'com.mikepenz:material-design-iconic-typeface:2.2.0.2@aar'     compile 'com.mikepenz:fontawesome-typeface:4.6.0.2@aar'      //facebook audience network     compile 'com.facebook.android:audience-network-sdk:4.13.0'      compile 'com.bartoszlipinski:recyclerviewheader2:2.0.1'     compile 'com.ms-square:etsyblur:0.1.3'     compile 'com.android.support:appcompat-v7:24.0.0'      // recyclerview     compile 'com.android.support:recyclerview-v7:24.0.0'      // material design     compile 'com.android.support:design:24.0.0'      // google analytics     compile 'com.google.android.gms:play-services-analytics:8.4.0'      // paypal purchasing todo change 'compile' (2k more methods..?)     compile files('libs/paypalandroidsdk-2.7.1.jar')      // module dependency on parseloginui library sources     compile project(':parseloginui')      // consider using these in future - wes feb 2016     //compile 'com.parse:parseui-login-android:0.0.1'     //compile 'com.parse:parseui-widget-android:0.0.1'      // parse     compile 'com.parse:parse-android:1.13.0'     compile 'com.parse:parsetwitterutils-android:1.10.5'     compile 'com.parse:parsefacebookutils-v4-android:1.10.4@aar'      // excluding bolts-android because parse-android uses bolts-tasks conflicts     // hint: use 'gradlew app:dependencies' inspect     compile('com.facebook.android:facebook-android-sdk:4.14.0') {         exclude module: 'bolts-android'         exclude module: 'bolts-tasks'     }      // butterknife     compile 'com.jakewharton:butterknife:8.4.0'     apt 'com.jakewharton:butterknife-compiler:8.4.0'      // apprater     compile files('libs/apprater.jar')      // retrofit http api     compile 'com.squareup.retrofit2:retrofit:2.0.0-beta4'     compile 'com.squareup.retrofit2:adapter-rxjava:2.0.0-beta4'     compile 'com.squareup.retrofit2:converter-gson:2.0.0-beta4'     compile 'com.squareup.okhttp3:logging-interceptor:3.0.1'      // reactivex     compile 'io.reactivex:rxjava:1.1.6'     compile 'io.reactivex:rxandroid:1.2.1'      // picasso image loading     compile 'com.squareup.picasso:picasso:2.5.2'      // stripe payment processing     compile 'com.stripe:stripe-android:1.0.4' } 

according butter knife readme need

buildscript {     repositories {         mavencentral()     }    dependencies {         classpath 'com.neenbedankt.gradle.plugins:android-apt:1.8'     } } 

in build.gradle file in root directory of android studio project.