Build Gradle Android studio Build Slow

android {
    productFlavors {
        // Define separate dev and prod product flavors.
        dev {
            // dev utilizes minSDKVersion = 21 to allow the Android gradle plugin
            // to pre-dex each module and produce an APK that can be tested on
            // Android Lollipop without time consuming dex merging processes.
            minSdkVersion 21
        }
        prod {
            // The actual minSdkVersion for the application.
            minSdkVersion 14
        }
    }
          ...
    buildTypes {
        release {
            runProguard true
            proguardFiles getDefaultProguardFile('proguard-android.txt'),
                                                 'proguard-rules.pro'
        }
        defaultConfig {
            applicationId "com.something.something"
            targetSdkVersion 23
            versionCode 1
            versionName "1.0.0"

            multiDexEnabled true
        }
    }
dependencies {
  compile 'com.android.support:multidex:1.0.1'
}

@Override
protected void attachBaseContext(Context base) {
    super.attachBaseContext(base);
    MultiDex.install(this);
}