diff --git a/bin/env.sh b/bin/env.sh
index cea9f2b657c780e346a2e8fd7a6c6919022da04f..65cf81f9a3d50dc578c3c2cd54ce2be86197ef0e 100755
--- a/bin/env.sh
+++ b/bin/env.sh
@@ -118,6 +118,7 @@ export DETECTOR_PREFIX="${LOCAL_PREFIX}/detector"
 mkdir -p ${DETECTOR_PREFIX}
 
 ## detector path: actual detector definition path
+export BEAMLINE_PATH="${DETECTOR_PREFIX}/${BEAMLINE_CONFIG}"
 export DETECTOR_PATH="${DETECTOR_PREFIX}/${DETECTOR}"
 
 ## build dir for ROOT to put its binaries etc.