diff --git a/build.gradle b/build.gradle
index ec4925c7..c56e0d85 100644
--- a/build.gradle
+++ b/build.gradle
@@ -1,7 +1,8 @@
 apply plugin: 'java'
 apply plugin: 'application'
 
-sourceCompatibility = "1.8";
+sourceCompatibility = JavaVersion.VERSION_1_7
+targetCompatibility = JavaVersion.VERSION_1_7
 
 mainClassName = 'cli.Main'