add missing definitions
diff --git a/pom.xml b/pom.xml
index cdb2ef0..5063c49 100644
--- a/pom.xml
+++ b/pom.xml
@@ -155,6 +155,8 @@
 		<tychoExtrasVersion>0.26.0</tychoExtrasVersion>
 
 		<xtext.version>2.11.0</xtext.version>
+		<sirius.version>4.1.3</sirius.version>
+		<sirius.repo.url>http://download.eclipse.org/sirius/updates/releases/${sirius.version}/${osbp.build.eclipse.platform.name}/</sirius.repo.url>
 
 		<osbp.skip.javadoc>false</osbp.skip.javadoc>
 		<osbp.javadoc.linksource>false</osbp.javadoc.linksource>