diff --git a/greenfoot/build.gradle b/greenfoot/build.gradle
index b60baf8d7..b8adbaf54 100644
--- a/greenfoot/build.gradle
+++ b/greenfoot/build.gradle
@@ -111,6 +111,7 @@ task greenfootJar(type: Jar) {
     }
     destinationDirectory = new File(sourceSets.main.output.resourcesDir, 'lib')
 }
+greenfootJar.dependsOn compileJava
 assemble.dependsOn greenfootJar
 assemble.dependsOn copyToLib