diff --git a/pom.xml b/pom.xml
index 1448d5a..ce0fc6b 100644
--- a/pom.xml
+++ b/pom.xml
@@ -23,6 +23,7 @@
 		<url>https://code-repo.d4science.org/gCubeSystem/${project.artifactId}</url>
 	</scm>
 	<properties>
+		<maven.compiler.source>1.8</maven.compiler.source>
 		<maven.compiler.target>1.8</maven.compiler.target>
 		<gwtVersion>2.8.1</gwtVersion>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>