gradle_diff.gradle

diff --git a/build.gradle b/build.gradle
index 2eb7fe4..d473a97 100644
--- a/build.gradle
+++ b/build.gradle
@@ -1,14 +1,14 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
 buildscript {
+    ext.kotlin_version = '1.1.1'
+    ext.gradle_plugin_version = '2.3.0'
     repositories {
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:2.3.0-beta3'
-        classpath 'me.tatarka:gradle-retrolambda:3.4.0'
-        // NOTE: Do not place your application dependencies here; they belong
-        // in the individual module build.gradle files
+        classpath "com.android.tools.build:gradle:$gradle_plugin_version"
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
     }
 }