diff --git a/bootstrap.sh b/bootstrap.sh
index 9f52ef7..8bf84cc 100644
--- a/bootstrap.sh
+++ b/bootstrap.sh
@@ -1,220 +1,223 @@
 #!/bin/bash
 ###
 # Part of a stupid script to backup some stuff
 #
 # This bootstrap.sh file does nothing by itself but loads useful stuff.
 #
 # This file is loaded from 'backup-everything.sh' or 'rotate.sh'
 #
 # Author:  2020, 2021 Valerio Bozzolan
 # License: MIT
 ##
 
 # current directory
-DIR="${BASH_SOURCE%/*}"
+export DIR="${BASH_SOURCE%/*}"
 if [[ ! -d "$DIR" ]]; then
 	DIR="$PWD";
 fi
 
 # check if the standard input is not a terminal
-INTERACTIVE=
+export INTERACTIVE=
 if [ -t 0 ]; then
 	INTERACTIVE=1
 fi
 
 #
 # Check if this is the quiet mode
 #
 # Default - not quite.
 #
 # Actually we are in quiet mode if it's not interactive.
 # This lazy behavior is to avoid stupid emails from the crontab
 # without the need to specify some --quiet etc.
 # Note that in quiet mode only WARN and ERROR messages are shown.
 # I've not created a --quiet flag because nobody is needing it.
 #
 # Edit your options - do not edit here.
 #
 #QUIET=
 
 #
 # Eventually write a log file
 #
 # Default - write a log file.
 #
 # Edit your options - do not edit here.
 #
-WRITELOG=1
+export WRITELOG=1
 
 # path to the instructions file
-INSTRUCTIONS="$DIR/backup-instructions.conf"
+export INSTRUCTIONS="$DIR/backup-instructions.conf"
 
 # path to the configuration file
-CONFIG="$DIR/options.conf"
+export CONFIG="$DIR/options.conf"
 
 # no config no party
-if [ ! -f $CONFIG ]; then
+if [ ! -f "$CONFIG" ]; then
 	echo "missing options expected in $CONFIG"
 	exit 1
 fi
 
 # default mysql commands
 #  --batch: avoid fancy columns (auto-enabled, but better to specify it)
 #  --silent: avoid the column name to be included
-MYSQL="mysql --batch --silent"
-MYSQLDUMP="mysqldump --routines --triggers"
+export MYSQL="mysql --batch --silent"
+export MYSQLDUMP="mysqldump --routines --triggers"
 
 # default rsync command
 # --archive:       Try to keep all the properties
 # --fuzzy:         Try to check if a file was renamed instead of delete and download a new one
 #                    It's efficient for example with log rotated files.
 # --delete:        Delete the destination files if not present in the source
 #                    NOTE: we want this behaviour but it's not a good idea toghether with --fuzzy
 #                          that's why we do not use --delete but we use the next flags
 # --delay-updates  Put all updated files into place at end (useful with fuzzy and delete modes)
 # --delete-delay   Delete after everything (useful with fuzzy and delete modes)
 #                    NOTE: sometime some data is kept in damn .~tmp~ directories
 #                          So we are deprecating --delete-delay, and going back to --delete
 #                          and so removing --fuzzy
 # --hard-links     Try to look for hard links during the transfer to do not copy separate files
 #RSYNC="rsync --archive --fuzzy --delay-updates --delete-delay --hard-links"
 
 # default rsync command
 # --archive:       Try to keep all the properties
 # --delete:        Delete the destination files if not present in the source
 # --hard-links     Try to look for hard links during the transfer to do not copy separate files
-RSYNC="rsync --archive --delete --hard-links"
+export RSYNC="rsync --archive --delete --hard-links"
 
 # rsync used in remote transfers
 # --compress       Use more CPU to save network bandwidth
-RSYNC_REMOTE="$RSYNC --compress"
+export RSYNC_REMOTE="$RSYNC --compress"
 
 # default base backup directory for all backups
-BASE="/home/backups"
+export BASE="/home/backups"
 
 # default box name
 BOX="$(hostname)"
+export BOX
 
 # set to 1 to avoid any disservice (e.g. systemctl stop/start)
-NO_DISSERVICE=
+export NO_DISSERVICE=
 
 # set to 1 to do nothing
-PORCELAIN=
+export PORCELAIN=
 
 # include the configuration to eventually override some options
+# shellcheck source=config.sh
 . "$CONFIG"
 
 # as default, if not interactive, set quite mode
 if [ -z "$QUIET" ] && [ "$INTERACTIVE" != 1 ]; then
 	QUIET=1
 fi
 
 # full pathnames to the backup directories
-BASEBOX="$BASE/$BOX"
-DAILY="$BASEBOX/daily"
-DAILY_FILES="$DAILY/files"
-DAILY_DATABASES="$DAILY/databases"
-DAILY_LASTLOG="$DAILY/last.log"
-DAILY_LASTTIME="$DAILY/last.timestamp"
+export BASEBOX="$BASE/$BOX"
+export DAILY="$BASEBOX/daily"
+export DAILY_FILES="$DAILY/files"
+export DAILY_DATABASES="$DAILY/databases"
+export DAILY_LASTLOG="$DAILY/last.log"
+export DAILY_LASTTIME="$DAILY/last.timestamp"
 
 # apply the porcelain to the rsync command
 if [ "$PORCELAIN" = 1 ]; then
 	RSYNC="$RSYNC --dry-run"
 	RSYNC_REMOTE="$RSYNC_REMOTE --dry-run"
 fi
 
 # set default backup_last_log() lines
 if [ -z "$BACKUP_LAST_LOG_LINES" ]; then
 	BACKUP_LAST_LOG_LINES=8000
 fi
 
 ###
 # Print something
 #
 # It also put the message in the backup directory
 #
 # @param string severity
 # @param string message
 #
 function printthis() {
 
-	local msg="[$(date)][$1] $2"
+	local msg
+	msg="[$(date)][$1] $2"
 
 	# print to standard output if it's not in quiet mode
 	if [ "$QUIET" != 1 ]; then
-		echo "$msg"
+		printf "%s\n" "$msg"
 	fi
 
 	# put in the log file if possible
 	if [ -f "$DAILY_LASTLOG" ] && [ "$WRITELOG" = 1 ]; then
-		echo "$msg" >> "$DAILY_LASTLOG"
+		printf "%s\n" "$msg" >> "$DAILY_LASTLOG"
 	fi
 }
 
 ###
 # Run an rsync
 #
 function copy() {
 
 	# show what we are doing
 	log "copy $*"
 
 	# run the rsync command
 	if [ "$PORCELAIN" != 1 ]; then
 		$RSYNC $@
 	fi
 }
 
 ###
 # Remove a pathname
 #
 function drop() {
 
 	# show what we are doing
 	log "drop $*"
 
 	# well, proceed... finger crossed... with some protections
 	if [ "$PORCELAIN" != 1 ]; then
 		rm --recursive --force --one-file-system --preserve-root -- $@
 	fi
 }
 
 ###
 # Move something somewhere
 #
 function move() {
 
 	# show what we are doing
 	log "move $*"
 
 	if [ "$PORCELAIN" != 1 ]; then
 		mv --force $@
 	fi
 }
 
 ###
 # Print a information message
 #
 # @param msg Message
 #
 function log() {
 	printthis INFO "$1"
 }
 
 ###
 # Print a warning message
 #
 # @param msg Message
 #
 function warn() {
 	printthis WARN "$1"
 }
 
 ###
 # Print an error message
 #
 # @param msg Message
 #
 function error() {
 	printthis ERROR "$1"
 }