diff --git a/_borg_backup_set_prefix_cleanup.sh b/_borg_backup_set_prefix_cleanup.sh
index c8843a3..5ef9ac1 100755
--- a/_borg_backup_set_prefix_cleanup.sh
+++ b/_borg_backup_set_prefix_cleanup.sh
@@ -31,16 +31,16 @@ MODULE_LIST="file gitea mysql pgsql zabbix"
 # -n for dry run test
 while getopts ":c:snd" opt; do
 	case "${opt}" in
-		c|config)
+		c) # config
 			BASE_FOLDER=${OPTARG};
 			;;
-		s|nosudo)
+		s) # nosudo
 			PGSQL_SUDO=0;
 			;;
-		d|debug)
+		d) # debug
 			DEBUG=1;
 			;;
-		n|dryrun)
+		n) # dryrun
 			DRYRUN=1;
 			;;
 		:)
@@ -64,9 +64,10 @@ if [ ! -f "${BASE_FOLDER}${SETTINGS_FILE}" ]; then
 	echo "Could not find: ${BASE_FOLDER}${SETTINGS_FILE}";
 	exit;
 fi;
+# shellcheck source="borg.backup.settings"
 . "${BASE_FOLDER}${SETTINGS_FILE}";
 
-if [ ! -z "${TARGET_BORG_PATH}" ]; then
+if [ -n "${TARGET_BORG_PATH}" ]; then
 	OPT_REMOTE="--remote-path="$(printf "%q" "${TARGET_BORG_PATH}");
 fi;
 export BORG_BASE_DIR="${BASE_FOLDER}";
@@ -82,16 +83,16 @@ for MODULE in ${MODULE_LIST}; do
 	TARGET_FOLDER=${TARGET_FOLDER#/}
 	# and add slash front and back and escape the path
 	TARGET_FOLDER=$(printf "%q" "/${TARGET_FOLDER}/");
-	if [ ! -z "${TARGET_USER}" ] && [ ! -z "${TARGET_HOST}" ] && [ ! -z "${TARGET_PORT}" ]; then
+	if [ -n "${TARGET_USER}" ] && [ -n "${TARGET_HOST}" ] && [ -n "${TARGET_PORT}" ]; then
 		TARGET_SERVER="ssh://${TARGET_USER}@${TARGET_HOST}:${TARGET_PORT}/";
 	# host/port
-	elif [ ! -z "${TARGET_HOST}" ] && [ ! -z "${TARGET_PORT}" ]; then
+	elif [ -n "${TARGET_HOST}" ] && [ -n "${TARGET_PORT}" ]; then
 		TARGET_SERVER="ssh://${TARGET_HOST}:${TARGET_PORT}/";
 	# user/host
-	elif [ ! -z "${TARGET_USER}" ] && [ ! -z "${TARGET_HOST}" ]; then
+	elif [ -n "${TARGET_USER}" ] && [ -n "${TARGET_HOST}" ]; then
 		TARGET_SERVER="${TARGET_USER}@${TARGET_HOST}:";
 	# host
-	elif [ ! -z "${TARGET_HOST}" ]; then
+	elif [ -n "${TARGET_HOST}" ]; then
 		TARGET_SERVER="${TARGET_HOST}:";
 	fi;
 	# we dont allow special characters, so we don't need to special escape it
@@ -112,14 +113,14 @@ for MODULE in ${MODULE_LIST}; do
 		if [ "${MODULE}" = "gitea" ]; then
 			# if just date, add gitea,
 			# else rename
-			if [ ! -z "${i##gitea*}" ]; then
+			if [ -n "${i##gitea*}" ]; then
 				target_name="${MODULE},${i}";
 			else
 				target_name=$(echo $i | sed -e 's/gitea-/gitea,/');
 			fi;
 		elif [ "${MODULE}" = "zabbix" ]; then
 			# if zabbix is missing, prefix
-			if [ ! -z "${i##zabbix*}" ]; then
+			if [ -n "${i##zabbix*}" ]; then
 				target_name="${MODULE},${i}";
 			else
 				target_name=$(echo $i | sed -e 's/zabbix-settings-/zabbix,settings-/');
diff --git a/borg.backup.file.sh b/borg.backup.file.sh
index 14d7791..600ff08 100755
--- a/borg.backup.file.sh
+++ b/borg.backup.file.sh
@@ -45,7 +45,7 @@ while read include_folder; do
 		echo "# [C] Comment: '${include_folder}'";
 	else
 		# skip if it is empty
-		if [ ! -z "${include_folder}" ]; then
+		if [ -n "${include_folder}" ]; then
 			# if this is a glob, do a double check that the base folder actually exists (?)
 			if [[ "${include_folder}" =~ $REGEX_GLOB ]]; then
 				# if this is */ then allow it
@@ -99,7 +99,7 @@ if [ -s "${BASE_FOLDER}${EXCLUDE_FILE}" ]; then
 	# remove non valid ones and warn
 	#TMP_EXCLUDE_FILE=$(mktemp --tmpdir ${EXCLUDE_FILE}.XXXXXXXX); # non mac
 	TMP_EXCLUDE_FILE=$(mktemp "${TEMPDIR}${EXCLUDE_FILE}".XXXXXXXX);
-	while read exclude_folder; do
+	while read -r exclude_folder; do
 		# strip any leading spaces from that folder
 		exclude_folder=$(echo "${exclude_folder}" | sed -e 's/^[ \t]*//');
 		# folder or any type of file is ok
@@ -108,7 +108,7 @@ if [ -s "${BASE_FOLDER}${EXCLUDE_FILE}" ]; then
 			echo "# [C] Comment: '${exclude_folder}'";
 		else
 			# skip if it is empty
-			if [ ! -z "${exclude_folder}" ]; then
+			if [ -n "${exclude_folder}" ]; then
 				# if it DOES NOT start with a / we assume free folder and add as is
 				if [[ "${exclude_folder}" != /* ]]; then
 					echo "${exclude_folder}" >> ${TMP_EXCLUDE_FILE};
diff --git a/borg.backup.functions.check.sh b/borg.backup.functions.check.sh
index 07d4a57..a695248 100644
--- a/borg.backup.functions.check.sh
+++ b/borg.backup.functions.check.sh
@@ -54,7 +54,7 @@ if [ ${RUN_CHECK} -eq 1 ]; then
 	OPT_GLOB="";
 	if [[ "${CHECK_PREFIX}" =~ $REGEX_GLOB ]]; then
 		OPT_GLOB="-a '${CHECK_PREFIX}'"
-	elif [ ! -z "${CHECK_PREFIX}" ]; then
+	elif [ -n "${CHECK_PREFIX}" ]; then
 		OPT_GLOB="-P ${CHECK_PREFIX}";
 	fi;
 	# debug/dryrun
diff --git a/borg.backup.functions.close.sh b/borg.backup.functions.close.sh
index 8730511..2168311 100644
--- a/borg.backup.functions.close.sh
+++ b/borg.backup.functions.close.sh
@@ -16,7 +16,7 @@ if [ $# -ge 1 ] && [ "$1" = "1" ]; then
 	printf "${PRINTF_MASTER_BLOCK}" "ERROR" "$(date +'%F %T')" "${MODULE}";
 else
 	# running time calculation
-	DURATION=$[ $(date +'%s')-$START ];
+	DURATION=$(( $(date +'%s')-START ));
 	echo "=== [Run time: $(convert_time ${DURATION})]";
 	printf "${PRINTF_MASTER_BLOCK}" "END" "$(date +'%F %T')" "${MODULE}";
 fi;
diff --git a/borg.backup.functions.compact.sh b/borg.backup.functions.compact.sh
index 565055d..3ed0f49 100644
--- a/borg.backup.functions.compact.sh
+++ b/borg.backup.functions.compact.sh
@@ -7,7 +7,7 @@ fi;
 
 # compact (only if BORG COMPACT is set)
 # only for borg 1.2
-if [ $(version $BORG_VERSION) -ge $(version "1.2.0") ]; then
+if [ "$(version "$BORG_VERSION")" -ge "$(version "1.2.0")" ]; then
 	RUN_COMPACT=0;
 	if [ $# -ge 1 ] && [ "$1" = "auto" ]; then
 		# strip any spaces and convert to int
@@ -18,11 +18,11 @@ if [ $(version $BORG_VERSION) -ge $(version "1.2.0") ]; then
 		fi;
 		# get current date timestmap
 		CURRENT_DATE=$(date +%s);
-		if [ ${COMPACT_INTERVAL} -eq 1 ]; then
+		if [ "${COMPACT_INTERVAL}" -eq 1 ]; then
 			RUN_COMPACT=1;
 			# set new compact time here
-			echo ${CURRENT_DATE} > "${BASE_FOLDER}${BACKUP_COMPACT_FILE}";
-		elif [ ${COMPACT_INTERVAL} -gt 1 ]; then
+			echo "${CURRENT_DATE}" > "${BASE_FOLDER}${BACKUP_COMPACT_FILE}";
+		elif [ "${COMPACT_INTERVAL}" -gt 1 ]; then
 			# else load last timestamp and check if today - last time stamp > days
 			if [ -z "${LAST_COMPACT_DATE}" ]; then
 				LAST_COMPACT_DATE=$(cat "${BASE_FOLDER}${BACKUP_COMPACT_FILE}" 2>/dev/null | sed -e 's/ //g');
@@ -32,25 +32,26 @@ if [ $(version $BORG_VERSION) -ge $(version "1.2.0") ]; then
 				LAST_COMPACT_DATE=0;
 			fi;
 			# if the difference greate than compact date, run. COMPACT INTERVAL is in days
-			if [ $(($CURRENT_DATE-$LAST_COMPACT_DATE)) -ge $((${COMPACT_INTERVAL}*86400)) ]; then
+			if [ $((CURRENT_DATE-LAST_COMPACT_DATE)) -ge $((COMPACT_INTERVAL*86400)) ]; then
 				RUN_COMPACT=1;
 				# set new compact time here
-				echo ${CURRENT_DATE} > "${BASE_FOLDER}${BACKUP_COMPACT_FILE}";
+				echo "${CURRENT_DATE}" > "${BASE_FOLDER}${BACKUP_COMPACT_FILE}";
 			fi;
 		fi;
-	elif [ ${COMPACT} -eq 1 ]; then
+	elif [ "${COMPACT}" -eq 1 ]; then
 		RUN_COMPACT=1;
 	fi;
 
 	if [ ${RUN_COMPACT} -eq 1 ]; then
 		# reset to normal IFS, so command works here
 		IFS=${_IFS};
+		# shellcheck disable=SC2059
 		printf "${PRINTF_SUB_BLOCK}" "COMPACT" "$(date +'%F %T')" "${MODULE}";
 		BORG_COMPACT="${BORG_COMMAND} compact ${OPT_REMOTE} -v ${OPT_PROGRESS} ${REPOSITORY}";
-		if [ ${DEBUG} -eq 1 ]; then
+		if [ "${DEBUG}" -eq 1 ]; then
 				echo "${BORG_COMPACT}";
 		fi;
-		if [ ${DRYRUN} -eq 0 ]; then
+		if [ "${DRYRUN}" -eq 0 ]; then
 			${BORG_COMPACT};
 		fi;
 	fi;
diff --git a/borg.backup.functions.info.sh b/borg.backup.functions.info.sh
index e18eed2..9e584ce 100644
--- a/borg.backup.functions.info.sh
+++ b/borg.backup.functions.info.sh
@@ -5,21 +5,21 @@ if [ -z "${MODULE}" ]; then
 	exit 1;
 fi;
 
-if [ ${INFO} -eq 1 ]; then
+if [ "${INFO}" -eq 1 ]; then
 	printf "${PRINTF_SUB_BLOCK}" "INFO" "$(date +'%F %T')" "${MODULE}";
 	# show command on debug or dry run
-	if [ ${DEBUG} -eq 1 ] || [ ${DRYRUN} -eq 1 ]; then
+	if [ "${DEBUG}" -eq 1 ] || [ "${DRYRUN}" -eq 1 ]; then
 		echo "export BORG_BASE_DIR=\"${BASE_FOLDER}\";${BORG_COMMAND} info ${OPT_REMOTE} ${REPOSITORY}";
 	fi;
 	# run info command if not a dry drun
-	if [ ${DRYRUN} -eq 0 ]; then
+	if [ "${DRYRUN}" -eq 0 ]; then
 		${BORG_COMMAND} info ${OPT_REMOTE} ${REPOSITORY};
 	fi;
 	if [ "${MODULE}" = "files" ]; then
-		if [ $FOLDER_OK -eq 1 ]; then
+		if [ "$FOLDER_OK" -eq 1 ]; then
 			echo "--- [Run command]:";
 			#IFS="#";
-			echo "export BORG_BASE_DIR=\"${BASE_FOLDER}\";${COMMAND} "${FOLDERS_Q[*]};
+			echo "export BORG_BASE_DIR=\"${BASE_FOLDER}\";${COMMAND} ${FOLDERS_Q[*]}";
 		else
 			echo "[!] No folders where set for the backup";
 		fi;
diff --git a/borg.backup.functions.init.sh b/borg.backup.functions.init.sh
index 5df244f..d7bbb5c 100644
--- a/borg.backup.functions.init.sh
+++ b/borg.backup.functions.init.sh
@@ -337,26 +337,26 @@ if [ ${PRINT} -eq 1 ] && ([ ${INIT} -eq 1 ] || [ ${VERIFY} -eq 1 ] || [ ${INFO}
 	exit 1;
 fi;
 # if tag is set, you can't have init, verify, info, etc
-if [ ! -z "${ONE_TIME_TAG}" ] && ([ ${PRINT} -eq 1 ] || [ ${INIT} -eq 1 ] || [ ${VERIFY} -eq 1 ] || [ ${INFO} -eq 1 ]); then
+if [ -n "${ONE_TIME_TAG}" ] && ([ ${PRINT} -eq 1 ] || [ ${INIT} -eq 1 ] || [ ${VERIFY} -eq 1 ] || [ ${INFO} -eq 1 ]); then
 	echo "Cannot have -T '${ONE_TIME_TAG}' option with -i info, -V verify, -I initialize or -P print option at the same time";
 	exit 1;
 fi;
 # verify only alphanumeric, no spaces, only underscore and dash
-if [ ! -z "${ONE_TIME_TAG}" ] && ! [[ "${ONE_TIME_TAG}" =~ ^[A-Za-z0-9_-]+$ ]]; then
+if [ -n "${ONE_TIME_TAG}" ] && ! [[ "${ONE_TIME_TAG}" =~ ^[A-Za-z0-9_-]+$ ]]; then
 	echo "One time tag '${ONE_TIME_TAG}' must be alphanumeric with dashes and underscore only.";
 	exit 1;
-elif [ ! -z "${ONE_TIME_TAG}" ]; then
+elif [ -n "${ONE_TIME_TAG}" ]; then
 	# all ok, attach . at the end
 	ONE_TIME_TAG=${ONE_TIME_TAG}".";
 fi;
 # if -D, cannot be with -T, -i, -C, -I, -P
-if [ ! -z "${DELETE_ONE_TIME_TAG}" ] && ([ ! -z "${ONE_TIME_TAG}" ] || [ ${PRINT} -eq 1 ] || [ ${INIT} -eq 1 ] || [ ${VERIFY} -eq 1 ] || [ ${INFO} -eq 1 ]); then
+if [ -n "${DELETE_ONE_TIME_TAG}" ] && ([ -n "${ONE_TIME_TAG}" ] || [ ${PRINT} -eq 1 ] || [ ${INIT} -eq 1 ] || [ ${VERIFY} -eq 1 ] || [ ${INFO} -eq 1 ]); then
 	echo "Cannot have -D delete tag option with -T one time tag, -i info, -V verify, -I initialize or -P print option at the same time";
 	exit 1;
 fi;
 # -D also must be in valid backup set format
 # ! [[ "${DELETE_ONE_TIME_TAG}" =~ ^[A-Za-z0-9_-]+\.${MODULE},(\*-)?[0-9]{4}-[0-9]{2}-[0-9]{2}T\*$ ]]
-if [ ! -z "${DELETE_ONE_TIME_TAG}" ] && ! [[ "${DELETE_ONE_TIME_TAG}" =~ ^[A-Za-z0-9_-]+\.${MODULE},([A-Za-z0-9_-]+-)?[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}$ ]] && ! [[ "${DELETE_ONE_TIME_TAG}" =~ ^[A-Za-z0-9_-]+\.${MODULE},(\*-)?[0-9]{4}-[0-9]{2}-[0-9]{2}T\*$ ]]; then
+if [ -n "${DELETE_ONE_TIME_TAG}" ] && ! [[ "${DELETE_ONE_TIME_TAG}" =~ ^[A-Za-z0-9_-]+\.${MODULE},([A-Za-z0-9_-]+-)?[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}$ ]] && ! [[ "${DELETE_ONE_TIME_TAG}" =~ ^[A-Za-z0-9_-]+\.${MODULE},(\*-)?[0-9]{4}-[0-9]{2}-[0-9]{2}T\*$ ]]; then
 	echo "Delete one time tag '${DELETE_ONE_TIME_TAG}' is in an invalid format. "
 	echo "Please verify existing tags with -P option."
 	echo "For a globing be sure it is in the format of: TAG.MODULE,*-YYYY-MM-DDT*";
@@ -369,7 +369,7 @@ if [ ${CHECK_VERIFY_DATA} -eq 1 ] && [ ${CHECK} -eq 0 ]; then
 	exit 1;
 fi;
 # -p can't be set without -C
-if [ ! -z "${CHECK_PREFIX}" ] && [ ${CHECK} -eq 0 ]; then
+if [ -n "${CHECK_PREFIX}" ] && [ ${CHECK} -eq 0 ]; then
 	echo "-p (pattern|glob) for check cannot be run without -C (Check) options";
 	exit 1;
 fi;
@@ -402,14 +402,14 @@ fi;
 . "${BASE_FOLDER}${SETTINGS_FILE}";
 
 # if OPTION SET overrides ALL others
-if [ ! -z "${OPT_BORG_EXECUTEABLE}" ]; then
+if [ -n "${OPT_BORG_EXECUTEABLE}" ]; then
 	BORG_COMMAND="${OPT_BORG_EXECUTEABLE}";
 	if [ ! -f "${BORG_COMMAND}" ]; then
 		echo "borg command not found with option -b: ${BORG_COMMAND}";
 		exit;
 	fi;
 # if in setting file, use this
-elif [ ! -z "${BORG_EXECUTEABLE}" ]; then
+elif [ -n "${BORG_EXECUTEABLE}" ]; then
 	BORG_COMMAND="${BORG_EXECUTEABLE}";
 	if [ ! -f "${BORG_COMMAND}" ]; then
 		echo "borg command not found with setting: ${BORG_COMMAND}";
@@ -449,7 +449,7 @@ if [ -z "${CHECK_INTERVAL}" ]; then
 	CHECK_INTERVAL="${DEFAULT_CHECK_INTERVAL}";
 fi;
 # deprecated name FORCE_CHECK, use FORCE_VERIFY instead
-if [ ! -z "${FORCE_CHECK}" ]; then
+if [ -n "${FORCE_CHECK}" ]; then
 	FORCE_VERIFY="${FORCE_CHECK}";
 fi;
 if [ -z "${FORCE_VERIFY}" ]; then
@@ -480,48 +480,48 @@ SETTINGS_FILE_SUB=$(echo "${SETTINGS_FILE}" | sed -e "s/\.settings/\.${MODULE,,}
 if [ -f "${BASE_FOLDER}${SETTINGS_FILE_SUB}" ]; then
 	. "${BASE_FOLDER}${SETTINGS_FILE_SUB}";
 	# if SUB_ set override master
-	if [ ! -z "${SUB_BACKUP_FILE}" ]; then
+	if [ -n "${SUB_BACKUP_FILE}" ]; then
 		BACKUP_FILE=${SUB_BACKUP_FILE}
 	fi;
 	# if sub backup set it set, override current
-	if [ ! -z "${SUB_BACKUP_SET}" ]; then
+	if [ -n "${SUB_BACKUP_SET}" ]; then
 		BACKUP_SET=${SUB_BACKUP_SET};
 	fi;
 	# ovrride compression
-	if [ ! -z "${SUB_COMPRESSION}" ]; then
+	if [ -n "${SUB_COMPRESSION}" ]; then
 		COMPRESSION=${SUB_COMPRESSION};
 	fi;
-	if [ ! -z "${SUB_COMPRESSION_LEVEL}" ]; then
+	if [ -n "${SUB_COMPRESSION_LEVEL}" ]; then
 		COMPRESSION_LEVEL=${SUB_COMPRESSION_LEVEL};
 	fi;
 	# compact interval override
-	if [ ! -z "${SUB_COMPACT_INTERVAL}" ]; then
+	if [ -n "${SUB_COMPACT_INTERVAL}" ]; then
 		COMPACT_INTERVAL="${SUB_COMPACT_INTERVAL}";
 	fi;
 	# override check interval
-	if [ ! -z "${SUB_CHECK_INTERVAL}" ]; then
+	if [ -n "${SUB_CHECK_INTERVAL}" ]; then
 		CHECK_INTERVAL="${SUB_CHECK_INTERVAL}";
 	fi;
 	# check override for keep time
-	if [ ! -z "${SUB_KEEP_LAST}" ]; then
+	if [ -n "${SUB_KEEP_LAST}" ]; then
 		KEEP_LAST=${SUB_KEEP_LAST};
 	fi;
-	if [ ! -z "${SUB_KEEP_HOURS}" ]; then
+	if [ -n "${SUB_KEEP_HOURS}" ]; then
 		KEEP_HOURS=${SUB_KEEP_HOURS};
 	fi;
-	if [ ! -z "${SUB_KEEP_DAYS}" ]; then
+	if [ -n "${SUB_KEEP_DAYS}" ]; then
 		KEEP_DAYS=${SUB_KEEP_DAYS};
 	fi;
-	if [ ! -z "${SUB_KEEP_WEEKS}" ]; then
+	if [ -n "${SUB_KEEP_WEEKS}" ]; then
 		KEEP_WEEKS=${SUB_KEEP_WEEKS};
 	fi;
-	if [ ! -z "${SUB_KEEP_MONTHS}" ]; then
+	if [ -n "${SUB_KEEP_MONTHS}" ]; then
 		KEEP_MONTHS=${SUB_KEEP_MONTHS};
 	fi;
-	if [ ! -z "${SUB_KEEP_YEARS}" ]; then
+	if [ -n "${SUB_KEEP_YEARS}" ]; then
 		KEEP_YEARS=${SUB_KEEP_YEARS};
 	fi;
-	if [ ! -z "${SUB_KEEP_WITHIN}" ]; then
+	if [ -n "${SUB_KEEP_WITHIN}" ]; then
 		KEEP_WITHIN=${SUB_KEEP_WITHIN};
 	fi;
 fi;
@@ -569,7 +569,7 @@ fi
 
 # log file set and check
 # option folder overrides all other folders
-if [ ! -z "${OPT_LOG_FOLDER}" ]; then
+if [ -n "${OPT_LOG_FOLDER}" ]; then
 	LOG_FOLDER="${OPT_LOG_FOLDER}";
 fi;
 # if empty folder set to default folder
@@ -631,15 +631,15 @@ function convert_time
 	done;
 
 	for ((i=0; i<${#output[@]}; i++)); do
-		if [ ${output[$i]} -gt 0 ] || [ ! -z "$time_string" ]; then
-			if [ ! -z "${time_string}" ]; then
+		if [ ${output[$i]} -gt 0 ] || [ -n "$time_string" ]; then
+			if [ -n "${time_string}" ]; then
 				time_string=${time_string}" ";
 			fi;
 			time_string=${time_string}${output[$i]}${timenames[$i]};
 		fi;
 	done;
-	if [ ! -z ${ms} ] && [ "${ms}" != "nan" ] && [ ${ms} -gt 0 ]; then
-		time_string=${time_string}" "${ms}"ms";
+	if [ -n "${ms}" ] && [ "${ms}" != "nan" ] && [ "${ms}" -gt 0 ]; then
+		time_string="${time_string} ${ms}ms";
 	fi;
 	# just in case the time is 0
 	if [ -z "${time_string}" ]; then
diff --git a/borg.backup.functions.verify.sh b/borg.backup.functions.verify.sh
index 594adf7..b13005e 100644
--- a/borg.backup.functions.verify.sh
+++ b/borg.backup.functions.verify.sh
@@ -30,7 +30,7 @@ printf "${PRINTF_INFO_STRING}" "Base folder" "${BASE_FOLDER}";
 printf "${PRINTF_INFO_STRING}" "Module init date" "${BACKUP_INIT_DATE}";
 # print last compact date if positive integer
 # only if borg > 1.2
-if [ $(version $BORG_VERSION) -ge $(version "1.2.0") ]; then
+if [ "$(version "$BORG_VERSION")" -ge "$(version "1.2.0")" ]; then
 	if [ "${COMPACT_INTERVAL##*[!0-9]*}" ]; then
 		printf "${PRINTF_INFO_STRING}" "Module compact interval" "${COMPACT_INTERVAL}";
 		if [ -f "${BASE_FOLDER}${BACKUP_COMPACT_FILE}" ]; then
@@ -57,15 +57,15 @@ fi;
 
 # if force verify is true set VERIFY to 1 unless INFO is 1
 # Needs bash 4.0 at lesat for this
-if [ "${FORCE_VERIFY,,}" = "true" ] && [ ${INFO} -eq 0 ]; then
+if [ "${FORCE_VERIFY,,}" = "true" ] && [ "${INFO}" -eq 0 ]; then
 	VERIFY=1;
-	if [ ${DEBUG} -eq 1 ]; then
+	if [ "${DEBUG}" -eq 1 ]; then
 		echo "Force repository verify";
 	fi;
 fi;
 
 # remote borg path
-if [ ! -z "${TARGET_BORG_PATH}" ]; then
+if [ -n "${TARGET_BORG_PATH}" ]; then
 	if [[ "${TARGET_BORG_PATH}" =~ \ |\' ]]; then
 		echo "Space found in ${TARGET_BORG_PATH}. Aborting";
 		echo "There are issues with passing on paths with spaces"
@@ -102,16 +102,16 @@ TARGET_SERVER='';
 # allow host only (if full setup in .ssh/config)
 # user@host OR ssh://user@host:port/ IF TARGET_PORT is set
 # user/host/port
-if [ ! -z "${TARGET_USER}" ] && [ ! -z "${TARGET_HOST}" ] && [ ! -z "${TARGET_PORT}" ]; then
+if [ -n "${TARGET_USER}" ] && [ -n "${TARGET_HOST}" ] && [ -n "${TARGET_PORT}" ]; then
 	TARGET_SERVER="ssh://${TARGET_USER}@${TARGET_HOST}:${TARGET_PORT}/";
 # host/port
-elif [ ! -z "${TARGET_HOST}" ] && [ ! -z "${TARGET_PORT}" ]; then
+elif [ -n "${TARGET_HOST}" ] && [ -n "${TARGET_PORT}" ]; then
 	TARGET_SERVER="ssh://${TARGET_HOST}:${TARGET_PORT}/";
 # user/host
-elif [ ! -z "${TARGET_USER}" ] && [ ! -z "${TARGET_HOST}" ]; then
+elif [ -n "${TARGET_USER}" ] && [ -n "${TARGET_HOST}" ]; then
 	TARGET_SERVER="${TARGET_USER}@${TARGET_HOST}:";
 # host
-elif [ ! -z "${TARGET_HOST}" ]; then
+elif [ -n "${TARGET_HOST}" ]; then
 	TARGET_SERVER="${TARGET_HOST}:";
 fi;
 # we dont allow special characters, so we don't need to special escape it
@@ -120,13 +120,13 @@ printf "${PRINTF_INFO_STRING}" "Repository" "${REPOSITORY}";
 
 # check if given compression name and level are valid
 OPT_COMPRESSION='';
-if [ ! -z "${COMPRESSION}" ]; then
+if [ -n "${COMPRESSION}" ]; then
 	# valid compression
 	if [ "${COMPRESSION}" = "lz4" ] || [ "${COMPRESSION}" = "zlib" ] || [ "${COMPRESSION}" = "lzma" ] || [ "${COMPRESSION}" = "zstd" ]; then
 		OPT_COMPRESSION="-C=${COMPRESSION}";
 		# if COMPRESSION_LEVEL, check it is a valid regex
 		# for zlib, zstd, lzma
-		if [ ! -z "${COMPRESSION_LEVEL}" ] && ([ "${COMPRESSION}" = "zlib" ] || [ "${COMPRESSION}" = "lzma" ] || [ "${COMPRESSION}" = "zstd" ]); then
+		if [ -n "${COMPRESSION_LEVEL}" ] && { [ "${COMPRESSION}" = "zlib" ] || [ "${COMPRESSION}" = "lzma" ] || [ "${COMPRESSION}" = "zstd" ]; }; then
 			MIN_COMPRESSION=0;
 			MAX_COMPRESSION=0;
 			case "${COMPRESSION}" in
@@ -177,7 +177,7 @@ KEEP_OPTIONS=();
 # keep info string (for files)
 KEEP_INFO="";
 # override standard keep for tagged backups
-if [ ! -z "${ONE_TIME_TAG}" ]; then
+if [ -n "${ONE_TIME_TAG}" ]; then
 	BACKUP_SET="{now:%Y-%m-%dT%H:%M:%S}";
 	# set empty to avoid problems
 	KEEP_OPTIONS=("");
@@ -185,32 +185,32 @@ else
 	# build options and info string,
 	# also flag BACKUP_SET check if hourly is set
 	BACKUP_SET_VERIFY=0;
-	if [ ${KEEP_LAST} -gt 0 ]; then
+	if [ "${KEEP_LAST}" -gt 0 ]; then
 		KEEP_OPTIONS+=("--keep-last=${KEEP_LAST}");
 		KEEP_INFO="${KEEP_INFO}, last: ${KEEP_LAST}";
 	fi;
-	if [ ${KEEP_HOURS} -gt 0 ]; then
+	if [ "${KEEP_HOURS}" -gt 0 ]; then
 		KEEP_OPTIONS+=("--keep-hourly=${KEEP_HOURS}");
 		KEEP_INFO="${KEEP_INFO}, hourly: ${KEEP_HOURS}";
 		BACKUP_SET_VERIFY=1;
 	fi;
-	if [ ${KEEP_DAYS} -gt 0 ]; then
+	if [ "${KEEP_DAYS}" -gt 0 ]; then
 		KEEP_OPTIONS+=("--keep-daily=${KEEP_DAYS}");
 		KEEP_INFO="${KEEP_INFO}, daily: ${KEEP_DAYS}";
 	fi;
-	if [ ${KEEP_WEEKS} -gt 0 ]; then
+	if [ "${KEEP_WEEKS}" -gt 0 ]; then
 		KEEP_OPTIONS+=("--keep-weekly=${KEEP_WEEKS}");
 		KEEP_INFO="${KEEP_INFO}, weekly: ${KEEP_WEEKS}";
 	fi;
-	if [ ${KEEP_MONTHS} -gt 0 ]; then
+	if [ "${KEEP_MONTHS}" -gt 0 ]; then
 		KEEP_OPTIONS+=("--keep-monthly=${KEEP_MONTHS}");
 		KEEP_INFO="${KEEP_INFO}, monthly: ${KEEP_MONTHS}";
 	fi;
-	if [ ${KEEP_YEARS} -gt 0 ]; then
+	if [ "${KEEP_YEARS}" -gt 0 ]; then
 		KEEP_OPTIONS+=("--keep-yearly=${KEEP_YEARS}");
 		KEEP_INFO="${KEEP_INFO}, yearly: ${KEEP_YEARS}";
 	fi;
-	if [ ! -z "${KEEP_WITHIN}" ]; then
+	if [ -n "${KEEP_WITHIN}" ]; then
 		# check for invalid string. can only be number + H|d|w|m|y
 		if [[ "${KEEP_WITHIN}" =~ ^[0-9]+[Hdwmy]{1}$ ]]; then
 			KEEP_OPTIONS+=("--keep-within=${KEEP_WITHIN}");
@@ -244,7 +244,7 @@ fi;
 if [ -f "${BASE_FOLDER}${BACKUP_LOCK_FILE}" ]; then
 	LOCK_PID=$(cat "${BASE_FOLDER}${BACKUP_LOCK_FILE}" 2>/dev/null);
 	# check if lock file pid has an active program attached to it
-	if [ -f /proc/${LOCK_PID}/cmdline ]; then
+	if [ -f "/proc/${LOCK_PID}/cmdline" ]; then
 		echo "Script is already running on PID: ${$}";
 		. "${DIR}/borg.backup.functions.close.sh" 1;
 		exit 1;
@@ -272,11 +272,11 @@ _BORG_PRUNE="${BORG_COMMAND} prune ${OPT_REMOTE} -v --list ${OPT_PROGRESS} ${DRY
 # set base path to config directory to keep cache/config separated
 export BORG_BASE_DIR="${BASE_FOLDER}";
 # ignore non encrypted access
-export BORG_UNKNOWN_UNENCRYPTED_REPO_ACCESS_IS_OK=${_BORG_UNKNOWN_UNENCRYPTED_REPO_ACCESS_IS_OK};
+export BORG_UNKNOWN_UNENCRYPTED_REPO_ACCESS_IS_OK="${_BORG_UNKNOWN_UNENCRYPTED_REPO_ACCESS_IS_OK}";
 # ignore moved repo access
-export BORG_RELOCATED_REPO_ACCESS_IS_OK=${_BORG_RELOCATED_REPO_ACCESS_IS_OK};
+export BORG_RELOCATED_REPO_ACCESS_IS_OK="${_BORG_RELOCATED_REPO_ACCESS_IS_OK}";
 # and for debug print that tout
-if [ ${DEBUG} -eq 1 ]; then
+if [ "${DEBUG}" -eq 1 ]; then
 	echo "export BORG_UNKNOWN_UNENCRYPTED_REPO_ACCESS_IS_OK=${_BORG_UNKNOWN_UNENCRYPTED_REPO_ACCESS_IS_OK};";
 	echo "export BORG_RELOCATED_REPO_ACCESS_IS_OK=${_BORG_RELOCATED_REPO_ACCESS_IS_OK};";
 	echo "export BORG_BASE_DIR=\"${BASE_FOLDER}\";";
@@ -288,10 +288,10 @@ COMMAND_INFO="${COMMAND_EXPORT}${BORG_COMMAND} info ${OPT_REMOTE} ${REPOSITORY}"
 # if this is user@host, we need to use ssh command to verify if the file is there
 # else a normal verify is ok
 # unless explicit given, verify is skipped
-if [ ${VERIFY} -eq 1 ] || [ ${INIT} -eq 1 ]; then
+if [ "${VERIFY}" -eq 1 ] || [ "${INIT}" -eq 1 ]; then
 	printf "${PRINTF_SUB_BLOCK}" "VERIFY" "$(date +'%F %T')" "${MODULE}";
-	if [ ! -z "${TARGET_SERVER}" ]; then
-		if [ ${DEBUG} -eq 1 ]; then
+	if [ -n "${TARGET_SERVER}" ]; then
+		if [ "${DEBUG}" -eq 1 ]; then
 			echo "${BORG_COMMAND} info ${OPT_REMOTE} ${REPOSITORY} 2>&1|grep \"Repository ID:\"";
 		fi;
 		# use borg info and verify if it returns "Repository ID:" in the first line
@@ -305,19 +305,19 @@ if [ ${VERIFY} -eq 1 ] || [ ${INIT} -eq 1 ]; then
 		INIT_REPOSITORY=1;
 	fi;
 	# if verrify but no init and repo is there but init file is missing set it
-	if [ ${VERIFY} -eq 1 ] && [ ${INIT} -eq 0 ] && [ ${INIT_REPOSITORY} -eq 0 ] &&
+	if [ "${VERIFY}" -eq 1 ] && [ "${INIT}" -eq 0 ] && [ "${INIT_REPOSITORY}" -eq 0 ] &&
 		[ ! -f "${BASE_FOLDER}${BACKUP_INIT_FILE}" ]; then
 		# write init file
 		echo "[!] Add missing init verify file";
-		echo "$(date +%s)" > "${BASE_FOLDER}${BACKUP_INIT_FILE}";
+		date +%s > "${BASE_FOLDER}${BACKUP_INIT_FILE}";
 	fi;
 	# end if verified but repository is not here
-	if [ ${VERIFY} -eq 1 ] && [ ${INIT} -eq 0 ] && [ ${INIT_REPOSITORY} -eq 1 ]; then
+	if [ "${VERIFY}" -eq 1 ] && [ "${INIT}" -eq 0 ] && [ "${INIT_REPOSITORY}" -eq 1 ]; then
 		echo "[! $(date +'%F %T')] No repository. Please run with -I flag to initialze repository";
 		. "${DIR}/borg.backup.functions.close.sh" 1;
 		exit 1;
 	fi;
-	if [ ${EXIT} -eq 1 ] && [ ${VERIFY} -eq 1 ] && [ ${INIT} -eq 0 ]; then
+	if [ "${EXIT}" -eq 1 ] && [ "${VERIFY}" -eq 1 ] && [ "${INIT}" -eq 0 ]; then
 		echo "Repository exists";
 		echo "For more information run:"
 		echo "${COMMAND_INFO}";
@@ -325,16 +325,16 @@ if [ ${VERIFY} -eq 1 ] || [ ${INIT} -eq 1 ]; then
 		exit;
 	fi;
 fi;
-if [ ${INIT} -eq 1 ] && [ ${INIT_REPOSITORY} -eq 1 ]; then
+if [ "${INIT}" -eq 1 ] && [ "${INIT_REPOSITORY}" -eq 1 ]; then
 	printf "${PRINTF_SUB_BLOCK}" "INIT" "$(date +'%F %T')" "${MODULE}";
-	if [ ${DEBUG} -eq 1 ] || [ ${DRYRUN} -eq 1 ]; then
+	if [ "${DEBUG}" -eq 1 ] || [ "${DRYRUN}" -eq 1 ]; then
 		echo "${BORG_COMMAND} init ${OPT_REMOTE} -e ${ENCRYPTION} ${OPT_VERBOSE} ${REPOSITORY}";
 	fi
-	if [ ${DRYRUN} -eq 0 ]; then
+	if [ "${DRYRUN}" -eq 0 ]; then
 		# should trap and exit properly here
 		${BORG_COMMAND} init ${OPT_REMOTE} -e ${ENCRYPTION} ${OPT_VERBOSE} ${REPOSITORY};
 		# write init file
-		echo "$(date +%s)" > "${BASE_FOLDER}${BACKUP_INIT_FILE}";
+		date +%s > "${BASE_FOLDER}${BACKUP_INIT_FILE}";
 		echo "Repository initialized";
 		echo "For more information run:"
 		echo "${COMMAND_INFO}";
@@ -342,7 +342,7 @@ if [ ${INIT} -eq 1 ] && [ ${INIT_REPOSITORY} -eq 1 ]; then
 	. "${DIR}/borg.backup.functions.close.sh";
 	# exit after init
 	exit;
-elif [ ${INIT} -eq 1 ] && [ ${INIT_REPOSITORY} -eq 0 ]; then
+elif [ "${INIT}" -eq 1 ] && [ "${INIT_REPOSITORY}" -eq 0 ]; then
 	echo "[! $(date +'%F %T')] Repository already initialized";
 	echo "For more information run:"
 	echo "${COMMAND_INFO}";
@@ -359,18 +359,18 @@ if [ ! -f "${BASE_FOLDER}${BACKUP_INIT_FILE}" ]; then
 fi;
 
 # PRINT OUT current data, only do this if REPO exists
-if [ ${PRINT} -eq 1 ]; then
+if [ "${PRINT}" -eq 1 ]; then
 	printf "${PRINTF_SUB_BLOCK}" "PRINT" "$(date +'%F %T')" "${MODULE}";
 	FORMAT="{archive:<45} {comment:6} {start} - {end} [{id}] ({username}@{hostname}){NL}"
 	# show command on debug or dry run
-	if [ ${DEBUG} -eq 1 ] || [ ${DRYRUN} -eq 1 ]; then
+	if [ "${DEBUG}" -eq 1 ] || [ "${DRYRUN}" -eq 1 ]; then
 		echo "export BORG_BASE_DIR=\"${BASE_FOLDER}\";${BORG_COMMAND} list ${OPT_REMOTE} --format ${FORMAT} ${REPOSITORY}";
 	fi;
 	# run info command if not a dry drun
-	if [ ${DRYRUN} -eq 0 ]; then
+	if [ "${DRYRUN}" -eq 0 ]; then
 		${BORG_COMMAND} list ${OPT_REMOTE} --format "${FORMAT}" ${REPOSITORY} ;
 	fi;
-	if [ ${VERBOSE} -eq 1 ]; then
+	if [ "${VERBOSE}" -eq 1 ]; then
 		echo "";
 		echo "Base command info:"
 		echo "export BORG_BASE_DIR=\"${BASE_FOLDER}\";${BORG_COMMAND} [COMMAND] ${OPT_REMOTE} ${REPOSITORY}::[BACKUP] [PATH]";
@@ -389,21 +389,21 @@ if [ ${PRINT} -eq 1 ]; then
 fi;
 
 # run borg compact command and exit
-if [ ${COMPACT} -eq 1 ]; then
+if [ "${COMPACT}" -eq 1 ]; then
 	. "${DIR}/borg.backup.functions.compact.sh";
 	. "${DIR}/borg.backup.functions.close.sh";
 	exit;
 fi;
 
 # run borg check command and exit
-if [ ${CHECK} -eq 1 ]; then
+if [ "${CHECK}" -eq 1 ]; then
 	. "${DIR}/borg.backup.functions.check.sh";
 	. "${DIR}/borg.backup.functions.close.sh";
 	exit;
 fi;
 
 # DELETE ONE TIME TAG
-if [ ! -z "${DELETE_ONE_TIME_TAG}" ]; then
+if [ -n "${DELETE_ONE_TIME_TAG}" ]; then
 	printf "${PRINTF_SUB_BLOCK}" "DELETE" "$(date +'%F %T')" "${MODULE}";
 	# if a "*" is inside we don't do ONE archive, but globbing via -a option
 	DELETE_ARCHIVE=""
@@ -415,12 +415,12 @@ if [ ! -z "${DELETE_ONE_TIME_TAG}" ]; then
 		DELETE_ARCHIVE="::"${DELETE_ONE_TIME_TAG};
 	fi
 	# if this is borg <1.2 OPT_LIST does not work
-	if [ $(version $BORG_VERSION) -lt $(version "1.2.0") ]; then
+	if [ "$(version "$BORG_VERSION")" -lt "$(version "1.2.0")" ]; then
 		OPT_LIST="";
 	fi;
 	# if exists, delete and exit
 	# show command on debug or dry run
-	if [ ${DEBUG} -eq 1 ]; then
+	if [ "${DEBUG}" -eq 1 ]; then
 		echo "${BORG_COMMAND} delete ${OPT_REMOTE} ${OPT_LIST} -s ${OPT_GLOB} ${REPOSITORY}${DELETE_ARCHIVE}";
 	fi;
 	# run delete command if not a dry drun
@@ -432,11 +432,11 @@ if [ ! -z "${DELETE_ONE_TIME_TAG}" ]; then
 	fi;
 	# if not a dry run, compact repository after delete
 	# not that compact only works on borg 1.2
-	if [ $(version $BORG_VERSION) -ge $(version "1.2.0") ]; then
-		if [ ${DRYRUN} -eq 0 ]; then
+	if [ "$(version "$BORG_VERSION")" -ge "$(version "1.2.0")" ]; then
+		if [ "${DRYRUN}" -eq 0 ]; then
 			${BORG_COMMAND} compact ${OPT_REMOTE} ${REPOSITORY};
 		fi;
-		if [ ${DEBUG} -eq 1 ]; then
+		if [ "${DEBUG}" -eq 1 ]; then
 			echo "${BORG_COMMAND} compact ${OPT_REMOTE} ${REPOSITORY}";
 		fi;
 	fi;
diff --git a/borg.backup.mysql.sh b/borg.backup.mysql.sh
index 6325ce9..637fbb3 100755
--- a/borg.backup.mysql.sh
+++ b/borg.backup.mysql.sh
@@ -86,7 +86,7 @@ EVENTDB="mysql"
 EVENTS="--events"
 
 # ALL IN ONE FILE or PER DATABASE FLAG
-if [ ! -z "${DATABASE_FULL_DUMP}" ]; then
+if [ -n "${DATABASE_FULL_DUMP}" ]; then
 	SCHEMA_ONLY='';
 	schema_flag='data';
 	if [ "${DATABASE_FULL_DUMP}" = "schema" ]; then
diff --git a/borg.backup.pgsql.sh b/borg.backup.pgsql.sh
index 8d5011d..1708566 100755
--- a/borg.backup.pgsql.sh
+++ b/borg.backup.pgsql.sh
@@ -32,7 +32,7 @@ BACKUP_LOCK_FILE="borg.backup.${MODULE}.lock";
 # if info print info and then abort run
 . "${DIR}/borg.backup.functions.info.sh";
 
-if [ ! -z "${DATABASE_USER}" ]; then
+if [ -n "${DATABASE_USER}" ]; then
 	DB_USER=${DATABASE_USER};
 else
 	DB_USER='postgres';
@@ -95,7 +95,7 @@ CONN_DB_HOST=''; # -h <host>
 CONN_DB_PORT=''; # -p <port>
 
 # ALL IN ONE FILE or PER DATABASE FLAG
-if [ ! -z "${DATABASE_FULL_DUMP}" ]; then
+if [ -n "${DATABASE_FULL_DUMP}" ]; then
 	SCHEMA_ONLY='';
 	schema_flag='data';
 	if [ "${DATABASE_FULL_DUMP}" = "schema" ]; then
diff --git a/borg.backup.zabbix.sh b/borg.backup.zabbix.sh
index ff6cc99..fc2ad03 100755
--- a/borg.backup.zabbix.sh
+++ b/borg.backup.zabbix.sh
@@ -26,7 +26,7 @@ BACKUP_LOCK_FILE="borg.backup.${MODULE}.lock";
 if [ -z "${ZABBIX_DUMP_BIN}" ]; then
 	ZABBIX_DUMP_BIN="/usr/local/bin/zabbix-dump";
 fi;
-if [ ! -z "${ZABBIX_CONFIG}" ] && [ ! -f "${ZABBIX_CONFIG}" ]; then
+if [ -n "${ZABBIX_CONFIG}" ] && [ ! -f "${ZABBIX_CONFIG}" ]; then
 	echo "[! $(date +'%F %T')] Cannot find zabbix config: ${ZABBIX_CONFIG}";
 	. "${DIR}/borg.backup.functions.close.sh" 1;
 	exit 1;
@@ -48,7 +48,7 @@ if [ ! -f "${ZABBIX_DUMP_BIN}" ]; then
 	exit 1;
 fi;
 # -i (ignore)/ -f (backup)
-if [ ! -z "${ZABBIX_UNKNOWN_TABLES}" ]; then
+if [ -n "${ZABBIX_UNKNOWN_TABLES}" ]; then
 	OPT_ZABBIX_UNKNOWN_TABLES="-f";
 else
 	OPT_ZABBIX_UNKNOWN_TABLES="-i";
diff --git a/borg.mount.sh b/borg.mount.sh
index ef980d7..abf40ed 100755
--- a/borg.mount.sh
+++ b/borg.mount.sh
@@ -33,7 +33,7 @@ function usage ()
 }
 
 # set options
-while getopts ":c:m:uf:h" opt do
+while getopts ":c:m:uf:h" opt; do
 	case "${opt}" in
 		c|config)
 			BASE_FOLDER=${OPTARG};
@@ -80,7 +80,7 @@ if [ ${UMOUNT} -eq 0 ]; then
 		. ${BASE_FOLDER}${SETTINGS_FILE}
 		# set the borg backup file base on the settings data
 		# if we have user/host then we build the ssh command
-		if [ ! -z "${TARGET_USER}" ] && [ ! -z "${TARGET_HOST}" ]; then
+		if [ -n "${TARGET_USER}" ] && [ -n "${TARGET_HOST}" ]; then
 			TARGET_SERVER=${TARGET_USER}"@"${TARGET_HOST}":";
 		fi;
 		REPOSITORY=${TARGET_SERVER}${TARGET_FOLDER}${BACKUP_FILE};
@@ -90,7 +90,7 @@ if [ ${UMOUNT} -eq 0 ]; then
 
 	# check that the repostiory exists
 	REPOSITORY_OK=0;
-	if [ ! -z "${TARGET_SERVER}" ]; then
+	if [ -n "${TARGET_SERVER}" ]; then
 		# remove trailing : for this
 		TARGET_SERVER=${TARGET_SERVER/:};
 		# use ssh command to check remote existense