Android kotlin y Room Persistences library not building

Intento usar Room con kotlin y nada funciona arroja lo siguiente:

Supported source version 'RELEASE_7' from annotation processor 'android.arch.lifecycle.LifecycleProcessor' less than -source '1.8' Supported source version 'RELEASE_7' from annotation processor 'android.arch.persistence.room.RoomProcessor' less than - source '1.8' The following options were not recognized by any processor: '[kapt.kotlin.generated]' 

En mi class Build.Gradle, tengo lo siguiente (Fuera de service, pero toda la información importante está aquí)

 //project build.gradle ext { versions = [ support: '25.3.1', dagger : '2.11', arch_comp : '1.0.0-alpha1' ] } //app build.gradle apply plugin: 'kotlin-kapt' compile "android.arch.lifecycle:runtime:$rootProject.versions.arch_comp" compile "android.arch.lifecycle:extensions:$rootProject.versions.arch_comp" kapt "android.arch.lifecycle:compiler:$rootProject.versions.arch_comp" compile "android.arch.persistence.room:runtime:$rootProject.versions.arch_comp" compile "android.arch.persistence.room:rxjava2:$rootProject.versions.arch_comp" kapt "android.arch.persistence.room:compiler:$rootProject.versions.arch_comp" 

Mi class de module

 @Entity(tableName = "groups") data class Group(@ColumnInfo(name = "group_name") var groupName: String = "", @ColumnInfo(name = "users") var users :ArrayList<String> = ArrayList<String>()) { @ColumnInfo(name = "id") @PrimaryKey(autoGenerate = true) var id: Long = 0 } 

Mi class Dao

 @Dao interface GroupDao { @Query("SELECT * FROM groups") fun getAll() : LiveData<ArrayList<Group>> @Query("SELECT * FROM groups WHERE group_name = :p0") fun getGroupByName(groupName: String) : Group //I also did this but with no succsess instade of the above @Query("SELECT * FROM groups WHERE group_name = :arg0") fun getGroupByName(groupName: String) : Group } 

¿Me estoy perdiendo algo o estoy haciendo algo mal?