diff --git a/api/build.gradle b/api/build.gradle
index fd0e92bac..d876e1f1f 100644
--- a/api/build.gradle
+++ b/api/build.gradle
@@ -14,6 +14,11 @@ sourceSets {
     }
 }
 
+java {
+    sourceCompatibility = JavaVersion.VERSION_1_8
+    targetCompatibility = JavaVersion.VERSION_1_8
+}
+
 dependencies {
     api 'com.google.code.gson:gson:2.8.6'
     api "com.google.guava:guava:${guavaVersion}"