diff --git a/scripts/_common.sh b/scripts/_common.sh
index 87f2374..c713c0b 100644
--- a/scripts/_common.sh
+++ b/scripts/_common.sh
@@ -24,7 +24,7 @@ else
     install_on_root=false
     path2=${path/#\//}/ # path=/xwiki -> xwiki/
     path3=${path/#\//} # path=/xwiki -> xwiki
-    web_inf_path="$install_dir"/webapps$path/WEB-INF
+    web_inf_path="$install_dir/webapps$path/WEB-INF"
 fi
 
 #=================================================
@@ -34,18 +34,18 @@ fi
 enable_super_admin() {
     super_admin_pwd=$(ynh_string_random)
     super_admin_config="xwiki.superadminpassword=$super_admin_pwd"
-    ynh_add_config --template=xwiki.cfg --destination=/etc/$app/xwiki_conf.cfg
-    ln -f /etc/$app/xwiki_conf.cfg "$web_inf_path"/xwiki.cfg
-    chmod 400 /etc/$app/xwiki_conf.cfg
-    chown "$app:$app" /etc/$app/xwiki_conf.cfg
+    ynh_add_config --template=xwiki.cfg --destination=/etc/"$app"/xwiki_conf.cfg
+    ln -f /etc/"$app"/xwiki_conf.cfg "$web_inf_path"/xwiki.cfg
+    chmod 400 /etc/"$app"/xwiki_conf.cfg
+    chown "$app:$app" /etc/"$app"/xwiki_conf.cfg
 }
 
 disable_super_admin() {
     super_admin_config='#'
-    ynh_add_config --template=xwiki.cfg --destination=/etc/$app/xwiki_conf.cfg
-    ln -f /etc/$app/xwiki_conf.cfg "$web_inf_path"/xwiki.cfg
-    chmod 400 /etc/$app/xwiki_conf.cfg
-    chown "$app:$app" /etc/$app/xwiki_conf.cfg
+    ynh_add_config --template=xwiki.cfg --destination=/etc/"$app"/xwiki_conf.cfg
+    ln -f /etc/"$app"/xwiki_conf.cfg "$web_inf_path"/xwiki.cfg
+    chmod 400 /etc/"$app"/xwiki_conf.cfg
+    chown "$app:$app" /etc/"$app"/xwiki_conf.cfg
 }
 
 install_exension() {
@@ -66,12 +66,12 @@ install_exension() {
     local status_raw
     local state_request
 
-    chmod 700 $temp_dir
-    chown root:root $temp_dir
+    chmod 700 "$temp_dir"
+    chown root:root "$temp_dir"
 
-    ynh_add_config --template=install_extensions.xml --destination=$temp_dir/install_extensions.xml
+    ynh_add_config --template=install_extensions.xml --destination="$temp_dir"/install_extensions.xml
     status_raw=$($curl -i --user "superadmin:$super_admin_pwd" -X PUT -H 'Content-Type: text/xml' "http://127.0.0.1:$port/${path2}rest/jobs?jobType=install&async=true" --upload-file $temp_dir/install_extensions.xml)
-    state_request=$(echo $status_raw | $xq -x '//jobStatus/ns2:state')
+    state_request=$(echo "$status_raw" | $xq -x '//jobStatus/ns2:state')
 
     while true; do
         sleep 5
@@ -152,14 +152,14 @@ install_source() {
     elif [ "$path" == /root ]; then
         ynh_die --message='Path "/root" not supported'
     elif [ "$path" != /xwiki ]; then
-        mv "$install_dir"/webapps/xwiki "$install_dir"/webapps$path
+        mv "$install_dir"/webapps/xwiki "$install_dir/webapps$path"
     fi
 }
 
 add_config() {
-    ynh_add_config --template=hibernate.cfg.xml --destination=/etc/$app/hibernate.cfg.xml
-    ynh_add_config --template=xwiki.cfg --destination=/etc/$app/xwiki_conf.cfg
-    ynh_add_config --template=xwiki.properties --destination=/etc/$app/xwiki_conf.properties
+    ynh_add_config --template=hibernate.cfg.xml --destination=/etc/"$app"/hibernate.cfg.xml
+    ynh_add_config --template=xwiki.cfg --destination=/etc/"$app"/xwiki_conf.cfg
+    ynh_add_config --template=xwiki.properties --destination=/etc/"$app"/xwiki_conf.properties
 
     # Note that using /etc/xwiki/xwiki.cfg or /etc/xwiki/xwiki.properties is hard coded on the application
     # And using this break multi instance feature so we must use an other path
@@ -172,16 +172,16 @@ set_permissions() {
     chmod -R u+rwX,o-rwx "$install_dir"
     chown -R "$app:$app" "$install_dir"
 
-    chmod -R u=rwX,g=rX,o= /etc/$app
-    chown -R "$app:$app" /etc/$app
+    chmod -R u=rwX,g=rX,o= /etc/"$app"
+    chown -R "$app:$app" /etc/"$app"
 
-    chown "$app:$app" -R /var/log/$app
-    chmod u=rwX,g=rX,o= -R /var/log/$app
+    chown "$app:$app" -R /var/log/"$app"
+    chmod u=rwX,g=rX,o= -R /var/log/"$app"
 
-    find $data_dir \(   \! -perm -o= \
-                    -o \! -user $app \
-                    -o \! -group $app \) \
-                -exec chown $app:$app {} \; \
+    find "$data_dir" \(   \! -perm -o= \
+                    -o \! -user "$app" \
+                    -o \! -group "$app" \) \
+                -exec chown "$app:$app" {} \; \
                 -exec chmod u=rwX,g=rX,o= {} \;
 }
 
diff --git a/scripts/backup b/scripts/backup
index de2e1ea..7d7515d 100755
--- a/scripts/backup
+++ b/scripts/backup
@@ -15,7 +15,7 @@ source /usr/share/yunohost/helpers
 #=================================================
 ynh_print_info --message="Declaring files to be backed up..."
 
-if systemctl is-active $app --quiet; then
+if systemctl is-active "$app" --quiet; then
     ynh_print_warn --message="It's hightly recommended to make your backup when the service is stopped. Please stop $app service with this command before to run the backup 'systemctl stop $app.service'"
 fi
 
diff --git a/scripts/change_url b/scripts/change_url
index 77b52b4..1fd1da4 100644
--- a/scripts/change_url
+++ b/scripts/change_url
@@ -16,7 +16,7 @@ source /usr/share/yunohost/helpers
 #=================================================
 ynh_script_progression --message="Stopping a systemd service..." --weight=1
 
-ynh_systemd_action --service_name=$app --action=stop
+ynh_systemd_action --service_name="$app" --action=stop
 
 #=================================================
 # MODIFY URL IN NGINX CONF
@@ -27,15 +27,15 @@ ynh_change_url_nginx_config
 
 ynh_script_progression --message="Updating xwiki configuration..." --weight=1
 
-if [ $new_path != $old_path ]; then
-    if $install_on_root; then
-        mv "$install_dir"/webapps$old_path "$install_dir"/webapps/root
+if [ "$new_path" != "$old_path" ]; then
+    if "$install_on_root"; then
+        mv "$install_dir/webapps$old_path" "$install_dir"/webapps/root
     elif [ "$path" == /root ]; then
         ynh_die --message='Path "/root" not supported'
     elif [ $old_path == / ]; then
-        mv "$install_dir"/webapps/root "$install_dir"/webapps$new_path
+        mv "$install_dir"/webapps/root "$install_dir/webapps$new_path"
     else
-        mv "$install_dir"/webapps$old_path "$install_dir"/webapps$new_path
+        mv "$install_dir/webapps$old_path" "$install_dir/webapps$new_path"
     fi
 fi
 add_config
@@ -48,7 +48,7 @@ set_permissions
 #=================================================
 ynh_script_progression --message="Starting a systemd service..." --weight=1
 
-ynh_systemd_action --service_name=$app --action=start --log_path=systemd --line_match="$systemd_match_start_line"
+ynh_systemd_action --service_name="$app" --action=start --log_path=systemd --line_match="$systemd_match_start_line"
 wait_xwiki_started
 
 #=================================================
diff --git a/scripts/install b/scripts/install
index 8231484..287e813 100755
--- a/scripts/install
+++ b/scripts/install
@@ -13,15 +13,15 @@ source /usr/share/yunohost/helpers
 # APP "BUILD" (DEPLOYING SOURCES, VENV, COMPILING ETC)
 #=================================================
 
-if [ -n "$(ls -A $data_dir)" ]; then
+if [ -n "$(ls -A "$data_dir")" ]; then
     old_data_dir_path="${data_dir}_$(date '+%Y%m%d.%H%M%S')"
     ynh_print_warn "Data directory was not empty. Data was moved to $old_data_dir_path"
-    mkdir -p $old_data_dir_path
+    mkdir -p "$old_data_dir_path"
     mv -t "$old_data_dir_path" "$data_dir"/*
 fi
 
 mkdir -p /var/log/"$app"
-mkdir -p /etc/$app
+mkdir -p /etc/"$app"
 
 #=================================================
 # DOWNLOAD, CHECK AND UNPACK SOURCE
@@ -61,9 +61,9 @@ ynh_use_logrotate --logfile="/var/log/$app"
 enable_super_admin
 
 # Start a systemd service
-ynh_systemd_action --service_name=$app --action=start --log_path=systemd --line_match="$systemd_match_start_line"
+ynh_systemd_action --service_name="$app" --action=start --log_path=systemd --line_match="$systemd_match_start_line"
 
-if [ $install_standard_flavor -eq 1 ]; then
+if [ "$install_standard_flavor" -eq 1 ]; then
     ynh_script_progression --message='Installing flavor...'
     wait_for_flavor_install
 fi
@@ -72,7 +72,7 @@ ynh_script_progression --message='Installing LDAP extension...' --weight=1
 install_exension 'org.xwiki.contrib.ldap:ldap-authenticator' "$ldap_version"
 
 # Disable super admin
-ynh_systemd_action --service_name=$app --action=stop
+ynh_systemd_action --service_name="$app" --action=stop
 disable_super_admin
 
 #=================================================
@@ -82,7 +82,7 @@ disable_super_admin
 #=================================================
 
 ynh_script_progression --message='Starting a systemd service...' --weight=1
-ynh_systemd_action --service_name=$app --action=start --log_path=systemd --line_match="$systemd_match_start_line"
+ynh_systemd_action --service_name="$app" --action=start --log_path=systemd --line_match="$systemd_match_start_line"
 wait_xwiki_started
 
 #=================================================
diff --git a/scripts/remove b/scripts/remove
index 8b5abd6..d0fad6f 100755
--- a/scripts/remove
+++ b/scripts/remove
@@ -17,10 +17,10 @@ source /usr/share/yunohost/helpers
 ynh_script_progression --message="Removing system configurations related to $app..." --weight=1
 
 # Remove the service from the list of services known by YunoHost (added from `yunohost service add`)
-if ynh_exec_warn_less yunohost service status $app >/dev/null
+if ynh_exec_warn_less yunohost service status "$app" >/dev/null
 then
 	ynh_script_progression --message="Removing $app service integration..." --weight=1
-	yunohost service remove $app
+	yunohost service remove "$app"
 fi
 
 ynh_secure_remove --file="/etc/$app"
diff --git a/scripts/restore b/scripts/restore
index a8ef1aa..4737f23 100755
--- a/scripts/restore
+++ b/scripts/restore
@@ -22,7 +22,7 @@ ynh_restore
 #=================================================
 ynh_script_progression --message="Restoring the database..." --weight=1
 
-ynh_psql_connect_as --user=$db_user --password=$db_pwd --database=$db_name < ./db.sql
+ynh_psql_connect_as --user="$db_user" --password="$db_pwd" --database="$db_name" < ./db.sql
 
 #=================================================
 # RESTORE SYSTEM CONFIGURATIONS
@@ -32,8 +32,8 @@ ynh_script_progression --message="Restoring system configurations related to $ap
 mkdir -p /var/log/"$app"
 set_permissions
 
-systemctl enable $app.service --quiet
-yunohost service add $app --description=XWiki --log="/var/log/$app/$app.log"
+systemctl enable "$app".service --quiet
+yunohost service add "$app" --description=XWiki --log="/var/log/$app/$app.log"
 
 ynh_use_logrotate --logfile="/var/log/$app"
 
@@ -44,7 +44,7 @@ ynh_use_logrotate --logfile="/var/log/$app"
 #=================================================
 ynh_script_progression --message="Reloading NGINX web server and $app's service..." --weight=1
 
-ynh_systemd_action --service_name=$app --action=start --log_path=systemd --line_match="$systemd_match_start_line"
+ynh_systemd_action --service_name="$app" --action=start --log_path=systemd --line_match="$systemd_match_start_line"
 wait_xwiki_started
 
 ynh_systemd_action --service_name=nginx --action=reload
diff --git a/scripts/upgrade b/scripts/upgrade
index 7a7bf68..92eb21d 100755
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -9,7 +9,7 @@
 source _common.sh
 source /usr/share/yunohost/helpers
 
-upgrade_type=$(ynh_check_app_version_changed)
+upgrade_type="$(ynh_check_app_version_changed)"
 
 if ynh_compare_current_package_version --comparison=le --version='14.10.8~ynh1'; then
     ynh_die --mesage='Upgrade from this version is not supported. Please backup and restore manually the data after a clean new install'
@@ -20,7 +20,7 @@ fi
 #=================================================
 ynh_script_progression --message='Stopping a systemd service..' --weight=1
 
-ynh_systemd_action --service_name=$app --action=stop --log_path="/var/log/$app/$app.log"
+ynh_systemd_action --service_name="$app" --action=stop --log_path="/var/log/$app/$app.log"
 
 #=================================================
 # "REBUILD" THE APP (DEPLOY NEW SOURCES, RERUN NPM BUILD...)
@@ -63,9 +63,9 @@ set_permissions
 enable_super_admin
 
 # Start a systemd service
-ynh_systemd_action --service_name=$app --action=start --log_path=systemd --line_match="$systemd_match_start_line"
+ynh_systemd_action --service_name="$app" --action=start --log_path=systemd --line_match="$systemd_match_start_line"
 
-if [ $install_standard_flavor -eq 1 ]; then
+if [ "$install_standard_flavor" -eq 1 ]; then
     ynh_script_progression --message='Upgrading flavor...'
     wait_for_flavor_install
 fi
@@ -74,7 +74,7 @@ ynh_script_progression --message='Upgrading LDAP extension...' --weight=1
 install_exension 'org.xwiki.contrib.ldap:ldap-authenticator' "$ldap_version"
 
 # Disable super admin
-ynh_systemd_action --service_name=$app --action=stop
+ynh_systemd_action --service_name="$app" --action=stop
 disable_super_admin
 
 #=================================================
@@ -84,7 +84,7 @@ disable_super_admin
 #=================================================
 
 ynh_script_progression --message='Starting a systemd service...' --weight=1
-ynh_systemd_action --service_name=$app --action=start --log_path=systemd --line_match="$systemd_match_start_line"
+ynh_systemd_action --service_name="$app" --action=start --log_path=systemd --line_match="$systemd_match_start_line"
 wait_xwiki_started
 
 #=================================================