diff --git a/start.sh b/start.sh
index 5f6a279..675fea5 100755
--- a/start.sh
+++ b/start.sh
@@ -12,21 +12,21 @@ NEXTCLOUD_DIR_CHOWN=${NEXTCLOUD_DIR_CHOWN:-1}
 NEXTCLOUD_SLEEP=${NEXTCLOUD_SLEEP:-30}
 
 # check if group already exists
-GRP_NAME=$(getent group ${USER_GID} )
+GRP_NAME=$(getent group "${USER_GID}" )
 if [ "${GRP_NAME}" ] ; then
-	USER_GROUP=$( echo ${GRP_NAME} | sed 's/\:.*//' )
+	USER_GROUP=$( echo "${GRP_NAME}" | sed 's/\:.*//' )
 else
 	# if not, we create the group
-	addgroup -g ${USER_GID} ${USER_GROUP}
+	addgroup -g "${USER_GID}" "${USER_GROUP}"
 fi
 
 # check if user already exists
-USR_NAME=$(getent passwd ${USER_UID} )
+USR_NAME=$(getent passwd "${USER_UID}" )
 if [ "${USR_NAME}" ] ; then
-	USER_NAME=$( echo ${USR_NAME} | sed 's/\:.*//' )
+	USER_NAME=$( echo "${USR_NAME}" | sed 's/\:.*//' )
 else
 	# if not, we create the user
-	adduser -s /bin/false -D -H -G ${USER_GROUP} -u ${USER_UID} ${USER_NAME}
+	adduser -s /bin/false -D -H -G "${USER_GROUP}" -u "${USER_UID}" "${USER_NAME}"
 fi
 
 # create dir if not exists (it should exist if you mapped it outside the container)
@@ -36,7 +36,7 @@ fi
 
 # replace data directory permissions
 if [ "${NEXTCLOUD_DIR_CHOWN}" = "1" ] ; then
-	chown -R ${USER_UID}:${USER_GID} "${NEXTCLOUD_DIR}"
+	chown -R "${USER_UID}":"${USER_GID}" "${NEXTCLOUD_DIR}"
 fi
 
 PARAMS=
@@ -70,6 +70,6 @@ PARAMS="${PARAMS} --non-interactive -u ${NEXTCLOUD_USERNAME} -p ${NEXTCLOUD_PASS
 
 # main loop
 while true; do
-	/bin/su -s /bin/sh ${USER_NAME} -c "/usr/bin/nextcloudcmd ${PARAMS}"
-	sleep ${NEXTCLOUD_SLEEP}
+	/bin/su -s /bin/sh "${USER_NAME}" -c "/usr/bin/nextcloudcmd ${PARAMS}"
+	sleep "${NEXTCLOUD_SLEEP}"
 done