diff --git a/build.gradle b/build.gradle
index e83acc52..c12f8c21 100644
--- a/build.gradle
+++ b/build.gradle
@@ -11,6 +11,9 @@ repositories {
   mavenLocal()
 }
 
+sourceCompatibility = 1.6
+targetCompatibility = 1.6
+
 configurations {
   compile {
     transitive = false