diff --git a/builder/build.sh b/builder/build.sh
index dd005d6..3b4e44d 100755
--- a/builder/build.sh
+++ b/builder/build.sh
@@ -178,6 +178,7 @@ export TARGET_HOSTNAME=${TARGET_HOSTNAME:-raspberrypi}
 
 export FIRST_USER_NAME=${FIRST_USER_NAME:-pi}
 export FIRST_USER_PASS=${FIRST_USER_PASS:-raspberry}
+export RELEASE=${RELEASE:-buster}
 export WPA_ESSID
 export WPA_PASSWORD
 export WPA_COUNTRY
diff --git a/builder/stage0/prerun.sh b/builder/stage0/prerun.sh
index 3b25783..cc29e5c 100755
--- a/builder/stage0/prerun.sh
+++ b/builder/stage0/prerun.sh
@@ -2,4 +2,4 @@
 
 if [ ! -d "${ROOTFS_DIR}" ]; then
 	bootstrap ${RELEASE} "${ROOTFS_DIR}" http://raspbian.raspberrypi.org/raspbian/
-fi
+fi
\ No newline at end of file