diff --git a/usr/local/share/bastille/bootstrap.sh b/usr/local/share/bastille/bootstrap.sh
index bfad535e..295ebf67 100644
--- a/usr/local/share/bastille/bootstrap.sh
+++ b/usr/local/share/bastille/bootstrap.sh
@@ -216,6 +216,8 @@ bootstrap_release() {
     if [ -f "${bastille_releasesdir}/${RELEASE}/COPYRIGHT" ]; then
         ## check distfiles list and skip existing cached files
         bastille_bootstrap_archives=$(echo "${bastille_bootstrap_archives}" | sed "s/base//")
+        # TODO check how to handle this
+        # shellcheck disable=SC2010
         bastille_cached_files=$(ls "${bastille_cachedir}/${RELEASE}" | grep -v "MANIFEST" | tr -d ".txz")
         for distfile in ${bastille_cached_files}; do
             bastille_bootstrap_archives=$(echo "${bastille_bootstrap_archives}" | sed "s/${distfile}//")
@@ -452,7 +454,7 @@ HW_MACHINE_ARCH=$(sysctl hw.machine_arch | awk '{ print $2 }')
 
 # bootstrapping from aarch64/arm64 Debian or Ubuntu require a different value for ARCH
 # create a new variable
-if [ "${HW_MACHINE_ARCH}" == "aarch64" ]; then
+if [ "${HW_MACHINE_ARCH}" = "aarch64" ]; then
     HW_MACHINE_ARCH_LINUX="arm64"
 else
     HW_MACHINE_ARCH_LINUX=${HW_MACHINE_ARCH}
diff --git a/usr/local/share/bastille/clone.sh b/usr/local/share/bastille/clone.sh
index 48a4417d..fee55737 100644
--- a/usr/local/share/bastille/clone.sh
+++ b/usr/local/share/bastille/clone.sh
@@ -58,6 +58,7 @@ validate_ip() {
     if [ -n "${ip6}" ]; then
         info "Valid: (${ip6})."
         IPX_ADDR="ip6.addr"
+        # shellcheck disable=SC2034
         IP6_MODE="new"
     else
         local IFS
@@ -104,8 +105,8 @@ update_jailconf_vnet() {
     bastille_jail_rc_conf="${bastille_jailsdir}/${NEWNAME}/root/etc/rc.conf"
 
     # Determine number of containers and define an uniq_epair
-    local list_jails_num=$(bastille list jails | wc -l | awk '{print $1}')
-    local num_range=$(expr "${list_jails_num}" + 1)
+    local list_jails_num="$(bastille list jails | wc -l | awk '{print $1}')"
+    local num_range="$(expr "${list_jails_num}" + 1)"
     jail_list=$(bastille list jail)
     for _num in $(seq 0 "${num_range}"); do
         if [ -n "${jail_list}" ]; then
@@ -125,7 +126,7 @@ update_jailconf_vnet() {
     sed -i '' "s|ifconfig_e0b_bastille.*_name|ifconfig_e0b_${uniq_epair}_name|" "${bastille_jail_rc_conf}"
 
     # If 0.0.0.0 set DHCP, else set static IP address
-    if [ "${IP}" == "0.0.0.0" ]; then
+    if [ "${IP}" = "0.0.0.0" ]; then
         sysrc -f "${bastille_jail_rc_conf}" ifconfig_vnet0="SYNCDHCP"
     else
         sysrc -f "${bastille_jail_rc_conf}" ifconfig_vnet0="inet ${IP}"
diff --git a/usr/local/share/bastille/destroy.sh b/usr/local/share/bastille/destroy.sh
index 9d9e9996..9bdb6057 100644
--- a/usr/local/share/bastille/destroy.sh
+++ b/usr/local/share/bastille/destroy.sh
@@ -172,7 +172,7 @@ destroy_rel() {
             if [ "${FORCE}" = "1" ]; then
                 ## remove cache on force
                 if [ -d "${bastille_cachedir}/${TARGET}" ]; then
-                    rm -rf "${bastille_cachedir}/${TARGET}"
+                    rm -rf "${bastille_cachedir:?}/${TARGET}"
                 fi
             fi
             echo
diff --git a/usr/local/share/bastille/import.sh b/usr/local/share/bastille/import.sh
index 391dfc9d..34cda5fc 100644
--- a/usr/local/share/bastille/import.sh
+++ b/usr/local/share/bastille/import.sh
@@ -79,7 +79,7 @@ while [ $# -gt 0 ]; do
             TARGET="${2}"
             shift
             ;;
-        -*|--*)
+        --*|-*)
             error_notify "Unknown Option."
             usage
             ;;
@@ -281,7 +281,7 @@ EOF
         >> "${bastille_jailsdir}/${TARGET_TRIM}/fstab"
 
         # Work with the symlinks
-        cd "${bastille_jailsdir}/${TARGET_TRIM}/root"
+        cd "${bastille_jailsdir}/${TARGET_TRIM}/root" || error_exit "Failed to change directory."
         update_symlinks
     else
         # Generate new empty fstab file
@@ -324,7 +324,7 @@ update_config() {
     >> "${bastille_jailsdir}/${TARGET_TRIM}/fstab"
 
     # Work with the symlinks
-    cd "${bastille_jailsdir}/${TARGET_TRIM}/root"
+    cd "${bastille_jailsdir}/${TARGET_TRIM}/root" || error_exit "Failed to change directory."
     update_symlinks
 }
 
@@ -377,7 +377,7 @@ update_symlinks() {
     for _link in ${SYMLINKS}; do
         if [ -L "${_link}" ]; then
             ln -sf /.bastille/${_link} ${_link}
-        elif [ "${ALLOW_EMPTY_DIRS_TO_BE_SYMLINKED:-0}" = "1" -a -d "${_link}" ]; then
+        elif [ "${ALLOW_EMPTY_DIRS_TO_BE_SYMLINKED:-0}" = "1" ] && [ -d "${_link}" ]; then
             # -F will enforce that the directory is empty and replaced by the symlink
             ln -sfF /.bastille/${_link} ${_link} || EXIT_CODE=$?
             if [ "${EXIT_CODE:-0}" != "0" ]; then
diff --git a/usr/local/share/bastille/service.sh b/usr/local/share/bastille/service.sh
index 23b8e589..92fa4f27 100644
--- a/usr/local/share/bastille/service.sh
+++ b/usr/local/share/bastille/service.sh
@@ -41,7 +41,7 @@ help|-h|--help)
     ;;
 esac
 
-if [ $# -lt 1 -o $# -gt 2 ]; then
+if [ $# -lt 1 ] || [ $# -gt 2 ]; then
     usage
 fi
 
diff --git a/usr/local/share/bastille/tags.sh b/usr/local/share/bastille/tags.sh
index de24044c..65ed802f 100644
--- a/usr/local/share/bastille/tags.sh
+++ b/usr/local/share/bastille/tags.sh
@@ -50,7 +50,7 @@ help|-h|--help)
     ;;
 esac
 
-if [ $# -lt 1 -o $# -gt 2 ]; then
+if [ $# -lt 1 ] || [ $# -gt 2 ]; then
     usage
 fi
 
diff --git a/usr/local/share/bastille/update.sh b/usr/local/share/bastille/update.sh
index 3bd033f8..4304a73a 100644
--- a/usr/local/share/bastille/update.sh
+++ b/usr/local/share/bastille/update.sh
@@ -143,9 +143,10 @@ template_update() {
 templates_update() {
     # Update all templates
     _updated_templates=0
-    if [ -d  ${bastille_templatesdir} ]; then
-        for _template_path in $(ls -d ${bastille_templatesdir}/*/*); do
-            if [ -d $_template_path/.git ]; then
+    if [ -d "${bastille_templatesdir}" ]; then
+        # shellcheck disable=SC2045
+        for _template_path in $(ls -d "${bastille_templatesdir}/*/*"); do
+            if [ -d "$_template_path/.git" ]; then
                 BASTILLE_TEMPLATE=$(echo "$_template_path" | awk -F / '{ print $(NF-1) "/" $NF }')
                 template_update