diff --git a/conf/layer.conf b/conf/layer.conf
index 379b74b..8077dec 100644
--- a/conf/layer.conf
+++ b/conf/layer.conf
@@ -1,8 +1,8 @@
 # We have a conf and classes directory, add to BBPATH
-BBPATH := "${BBPATH}:${LAYERDIR}"
+BBPATH .= ":${LAYERDIR}"
 
 # We have a packages directory, add to BBFILES
-BBFILES := "${BBFILES} ${LAYERDIR}/recipes-*/*/*.bb \
+BBFILES += "${LAYERDIR}/recipes-*/*/*.bb \
             ${LAYERDIR}/recipes-*/*/*.bbappend"
 
 BBFILE_COLLECTIONS += "fsl-arm-extra"