diff --git a/build.gradle b/build.gradle
index 48791e21..04b8a0af 100644
--- a/build.gradle
+++ b/build.gradle
@@ -33,6 +33,10 @@ allprojects {
     apply plugin: 'kotlin'
     apply plugin: 'com.diffplug.spotless'
 
+    java {
+        targetCompatibility = JavaVersion.VERSION_1_8
+    }
+
     compileJava {
         options.release = 8
     }