diff --git a/scripts/change_url b/scripts/change_url
index 8c014a5..e84a828 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..."
 
-ynh_systemd_action --service_name=$app --action="stop" --log_path="systemd"
+ynh_systemd_action --service_name="$app" --action="stop" --log_path="systemd"
 
 #=================================================
 # MODIFY URL IN NGINX CONF
@@ -33,7 +33,7 @@ ynh_change_url_nginx_config
 ynh_script_progression --message="Starting a systemd service..."
 
 # Start a systemd service
-ynh_systemd_action --service_name=$app --action="start" --log_path="systemd" --line_match="Listening for"
+ynh_systemd_action --service_name="$app" --action="start" --log_path="systemd" --line_match="Listening for"
 
 #=================================================
 # END OF SCRIPT
diff --git a/scripts/install b/scripts/install
index 461ae0a..3d7f9b1 100644
--- a/scripts/install
+++ b/scripts/install
@@ -13,14 +13,14 @@ source /usr/share/yunohost/helpers
 # RETRIEVE ARGUMENTS FROM THE MANIFEST
 #=================================================
 
-email=$(ynh_user_get_info --username=$admin --key=mail)
+email=$(ynh_user_get_info --username="$admin" --key=mail)
 
 #=================================================
 # CHECK IF THE APP CAN BE INSTALLED WITH THESE ARGS
 #=================================================
 ynh_script_progression --message="Validating installation parameters..."
 
-if [[ $admin < 5 ]]; then
+if [[ $admin -lt 5 ]]; then
     ynh_die --message="Admin username minimum length is 5"
 fi
 
@@ -30,7 +30,7 @@ fi
 
 chmod 750 "$install_dir"
 chmod -R o-rwx "$install_dir"
-chown -R $app:www-data "$install_dir"
+chown -R "$app:www-data" "$install_dir"
 
 #=================================================
 # NGINX CONFIGURATION
@@ -40,9 +40,9 @@ ynh_script_progression --message="Configuring NGINX web server..."
 # Create a dedicated NGINX config
 ynh_add_nginx_config
 
-systemctl enable $app.service --quiet
+systemctl enable "$app.service" --quiet
 
-yunohost service add $app --description="Web-based Game Server Management System" --log="/var/log/$app/$app.log"
+yunohost service add "$app" --description="Web-based Game Server Management System" --log="/var/log/$app/$app.log"
 
 #=================================================
 # SPECIFIC SETUP
@@ -54,9 +54,9 @@ ynh_script_progression --message="Adding a configuration file..."
 ynh_add_config --template="config.json" --destination="/etc/$app/config.json"
 
 chmod 650 "/etc/$app/config.json"
-chown $app:$app "/etc/$app/config.json"
+chown "$app:$app" "/etc/$app/config.json"
 
-pufferpanel user add --admin --email=$email --name=$admin --password=$password
+pufferpanel user add --admin --email="$email" --name="$admin" --password="$password"
 
 #=================================================
 # GENERIC FINALIZATION
@@ -66,7 +66,7 @@ pufferpanel user add --admin --email=$email --name=$admin --password=$password
 ynh_script_progression --message="Starting a systemd service..." --weight=1
 
 # Start a systemd service
-ynh_systemd_action --service_name=$app --action="start" --log_path="systemd" --line_match="Listening for"
+ynh_systemd_action --service_name="$app" --action="start" --log_path="systemd" --line_match="Listening for"
 
 #=================================================
 # END OF SCRIPT
diff --git a/scripts/remove b/scripts/remove
index 23a0a4c..da0e4a3 100644
--- a/scripts/remove
+++ b/scripts/remove
@@ -16,10 +16,10 @@ source /usr/share/yunohost/helpers
 #=================================================
 
 # 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..."
-	yunohost service remove $app
+	yunohost service remove "$app"
 fi
 
 # Remove the dedicated NGINX config
diff --git a/scripts/restore b/scripts/restore
index 39470e1..3f07df1 100644
--- a/scripts/restore
+++ b/scripts/restore
@@ -19,14 +19,14 @@ ynh_script_progression --message="Restoring the app main directory..." --weight=
 ynh_restore_file --origin_path="$install_dir"
 
 chmod -R o-rwx "$install_dir"
-chown -R $app:www-data "$install_dir"
+chown -R "$app:www-data" "$install_dir"
 
 #=================================================
 # RESTORE THE POSTGRESQL DATABASE
 #=================================================
 ynh_script_progression --message="Restoring the PostgreSQL database..." --weight=6
 
-ynh_psql_execute_file_as_root --file="./db.sql" --database=$db_name
+ynh_psql_execute_file_as_root --file="./db.sql" --database="$db_name"
 
 #=================================================
 # RESTORE VARIOUS FILES
@@ -38,9 +38,9 @@ ynh_restore_file --origin_path="/var/lib/$app/"
 
 ynh_restore_file --origin_path="/etc/nginx/conf.d/$domain.d/$app.conf"
 
-systemctl enable $app.service --quiet
+systemctl enable "$app.service" --quiet
 
-yunohost service add $app --description="Web-based Game Server Management System" --log="/var/log/$app/$app.log"
+yunohost service add "$app" --description="Web-based Game Server Management System" --log="/var/log/$app/$app.log"
 
 #=================================================
 # GENERIC FINALIZATION
@@ -49,7 +49,7 @@ yunohost service add $app --description="Web-based Game Server Management System
 #=================================================
 ynh_script_progression --message="Reloading NGINX web server and $app's service..." --weight=1
 
-ynh_systemd_action --service_name=$app --action="start" --log_path="systemd" --line_match="Listening for"
+ynh_systemd_action --service_name="$app" --action="start" --log_path="systemd" --line_match="Listening for"
 
 ynh_systemd_action --service_name=nginx --action=reload
 
diff --git a/scripts/upgrade b/scripts/upgrade
index 41f4066..66f3369 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -13,7 +13,7 @@ source /usr/share/yunohost/helpers
 # RETRIEVE ARGUMENTS FROM THE MANIFEST
 #=================================================
 
-email=$(ynh_user_get_info --username=$admin --key=mail)
+email=$(ynh_user_get_info --username="$admin" --key=mail)
 
 #=================================================
 # CHECK VERSION
@@ -28,7 +28,7 @@ upgrade_type=$(ynh_check_app_version_changed)
 #=================================================
 ynh_script_progression --message="Stopping a systemd service..."
 
-ynh_systemd_action --service_name=$app --action="stop" --log_path="systemd"
+ynh_systemd_action --service_name="$app" --action="stop" --log_path="systemd"
 
 #=================================================
 # UPGRADE DEPENDENCIES
@@ -36,7 +36,7 @@ ynh_systemd_action --service_name=$app --action="stop" --log_path="systemd"
 
 chmod 750 "$install_dir"
 chmod -R o-rwx "$install_dir"
-chown -R $app:www-data "$install_dir"
+chown -R "$app:www-data" "$install_dir"
 
 #=================================================
 # REAPPLY SYSTEM CONFIGURATIONS
@@ -46,9 +46,9 @@ ynh_script_progression --message="Upgrading system configurations related to $ap
 # Create a dedicated NGINX config
 ynh_add_nginx_config
 
-systemctl enable $app.service --quiet
+systemctl enable "$app.service" --quiet
 
-yunohost service add $app --description="Web-based Game Server Management System" --log="/var/log/$app/$app.log"
+yunohost service add "$app" --description="Web-based Game Server Management System" --log="/var/log/$app/$app.log"
 
 #=================================================
 # UPDATE A CONFIG FILE
@@ -58,14 +58,14 @@ ynh_script_progression --message="Updating a configuration file..."
 ynh_add_config --template="config.json" --destination="/etc/$app/config.json"
 
 chmod 650 "/etc/$app/config.json"
-chown $app:$app "/etc/$app/config.json"
+chown "$app:$app" "/etc/$app/config.json"
 
 #=================================================
 # START SYSTEMD SERVICE
 #=================================================
 ynh_script_progression --message="Starting a systemd service..."
 
-ynh_systemd_action --service_name=$app --action="start" --log_path="systemd" --line_match="Listening for"
+ynh_systemd_action --service_name="$app" --action="start" --log_path="systemd" --line_match="Listening for"
 
 #=================================================
 # END OF SCRIPT