diff --git a/scripts/change_url b/scripts/change_url
index 8cb79c0..d91fc78 100644
--- a/scripts/change_url
+++ b/scripts/change_url
@@ -40,8 +40,9 @@ domain="$new_domain"
 sub_path_only="$(if [[ "$path" == "/" ]]; then echo '# ' ; else echo ''; fi)"
 
 ynh_add_config --template="../conf/ihatemoney.cfg" --destination="$install_dir/ihatemoney.cfg"
+
 chmod 640 "$install_dir/ihatemoney.cfg"
-chown $app:$app "$install_dir/ihatemoney.cfg"
+chown "$app:$app" "$install_dir/ihatemoney.cfg"
 
 #=================================================
 # GENERIC FINALISATION
@@ -51,7 +52,7 @@ chown $app:$app "$install_dir/ihatemoney.cfg"
 ynh_script_progression --message="Starting a systemd service..." --weight=5
 
 # Start a systemd service
-ynh_systemd_action --service_name=$app --action="start"
+ynh_systemd_action --service_name="$app" --action="start"
 wait_gunicorn_start
 
 #=================================================
diff --git a/scripts/install b/scripts/install
index ff94957..16f5284 100755
--- a/scripts/install
+++ b/scripts/install
@@ -19,10 +19,6 @@ ynh_script_progression --message="Building venv..." --weight=6
 __ynh_python_venv_setup --venv_dir="$install_dir/venv" --packages "${pip_dependencies[*]}"
 python_venv_site_packages=$(__ynh_python_venv_get_site_packages_dir -d "$install_dir/venv")
 
-chmod 750 "$install_dir"
-chmod -R o-rwx "$install_dir"
-chown -R $app:www-data "$install_dir"
-
 #=================================================
 # NGINX CONFIGURATION
 #=================================================
@@ -39,26 +35,23 @@ ynh_script_progression --message="Adding a configuration file..."
 
 # Secret key for cookies encryption.
 secret_key=$(ynh_string_random --length=32)
-ynh_app_setting_set --app=$app --key=secret_key --value=$secret_key
+ynh_app_setting_set --app="$app" --key=secret_key --value="$secret_key"
 
 hashed_password=$(_hash_password "$password")
-ynh_secure_remove --file="$install_dir/key.txt"
-ynh_app_setting_set --app=$app --key=hashed_password --value=$hashed_password
-
-ynh_add_config --template="../conf/gunicorn.conf.py" --destination="$install_dir/gunicorn.conf.py"
-chmod 640 "$install_dir/gunicorn.conf.py"
-chown $app:$app "$install_dir/gunicorn.conf.py"
+ynh_app_setting_set --app="$app" --key=hashed_password --value="$hashed_password"
 
 # Allows to comment some config lines if not using sub path
 sub_path_only="$(if [[ "$path" == "/" ]]; then echo '# ' ; else echo ''; fi)"
 
+ynh_add_config --template="../conf/gunicorn.conf.py" --destination="$install_dir/gunicorn.conf.py"
 ynh_add_config --template="../conf/ihatemoney.cfg" --destination="$install_dir/ihatemoney.cfg"
-chmod 640 "$install_dir/ihatemoney.cfg"
-chown $app:$app "$install_dir/ihatemoney.cfg"
+
+chmod -R o-rwx "$install_dir"
+chown -R "$app:$app" "$install_dir"
 
 # Configure log directory
 mkdir -p "/var/log/$app"
-chown -R $app:$app "/var/log/$app"
+chown -R "$app:$app" "/var/log/$app"
 
 #=================================================
 # SETUP SYSTEMD
@@ -75,7 +68,7 @@ ynh_add_systemd_config
 #=================================================
 ynh_script_progression --message="Integrating service in YunoHost..." --weight=1
 
-yunohost service add $app --description="$app daemon for IHateMoney" --log=systemd
+yunohost service add "$app" --description="$app daemon for IHateMoney" --log=systemd
 
 #=================================================
 # START SYSTEMD SERVICE
@@ -83,7 +76,7 @@ yunohost service add $app --description="$app daemon for IHateMoney" --log=syste
 ynh_script_progression --message="Starting a systemd service..." --weight=1
 
 # Start a systemd service
-ynh_systemd_action --service_name=$app --action="start" --line_match="Listening at"
+ynh_systemd_action --service_name="$app" --action="start" --line_match="Listening at"
 wait_gunicorn_start
 
 #=================================================
diff --git a/scripts/remove b/scripts/remove
index c4b2cb9..9ced659 100755
--- a/scripts/remove
+++ b/scripts/remove
@@ -14,20 +14,15 @@ source /usr/share/yunohost/helpers
 #=================================================
 # REMOVE SERVICE INTEGRATION IN YUNOHOST
 #=================================================
+ynh_script_progression --message="Removing $app service integration..." --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
-then
-    ynh_script_progression --message="Removing $app service integration..." --weight=1
-    yunohost service remove $app
-fi
+yunohost service remove "$app"
 
 #=================================================
 # STOP AND REMOVE SERVICE
 #=================================================
 ynh_script_progression --message="Stopping and removing the systemd service..." --weight=1
 
-# Remove the dedicated systemd config
 ynh_remove_systemd_config
 
 #=================================================
@@ -35,7 +30,6 @@ ynh_remove_systemd_config
 #=================================================
 ynh_script_progression --message="Removing NGINX web server configuration..." --weight=1
 
-# Remove the dedicated NGINX config
 ynh_remove_nginx_config
 
 #=================================================
diff --git a/scripts/restore b/scripts/restore
index 7a38992..0c9dd41 100755
--- a/scripts/restore
+++ b/scripts/restore
@@ -17,10 +17,6 @@ ynh_script_progression --message="Restoring the app main directory..." --weight=
 
 ynh_restore_file --origin_path="$install_dir"
 
-chmod 750 "$install_dir"
-chmod -R o-rwx "$install_dir"
-chown -R $app:www-data "$install_dir"
-
 #=================================================
 # SPECIFIC RESTORATION
 #=================================================
@@ -35,7 +31,7 @@ ynh_restore_file --origin_path="/etc/nginx/conf.d/$domain.d/$app.conf"
 #=================================================
 ynh_script_progression --message="Restoring the MySQL database..." --weight=1
 
-ynh_mysql_connect_as --user=$db_user --password=$db_pwd --database=$db_name < ./db.sql
+ynh_mysql_connect_as --user="$db_user" --password="$db_pwd" --database="$db_name" < ./db.sql
 
 #=================================================
 # RESTORE SYSTEMD
@@ -43,7 +39,7 @@ ynh_mysql_connect_as --user=$db_user --password=$db_pwd --database=$db_name < ./
 ynh_script_progression --message="Restoring the systemd configuration..." --weight=1
 
 ynh_restore_file --origin_path="/etc/systemd/system/$app.service"
-systemctl enable $app.service --quiet
+systemctl enable "$app.service" --quiet
 
 #=================================================
 # RESTORE LOG
@@ -56,14 +52,14 @@ ynh_restore_file --origin_path="/var/log/$app"
 #=================================================
 ynh_script_progression --message="Integrating service in YunoHost..." --weight=1
 
-yunohost service add $app --description="$app daemon for IHateMoney" --log=systemd
+yunohost service add "$app" --description="$app daemon for IHateMoney" --log=systemd
 
 #=================================================
 # START SYSTEMD SERVICE
 #=================================================
 ynh_script_progression --message="Starting a systemd service..." --weight=1
 
-ynh_systemd_action --service_name=$app --action="start" --line_match="Listening at"
+ynh_systemd_action --service_name="$app" --action="start" --line_match="Listening at"
 wait_gunicorn_start
 
 #=================================================
diff --git a/scripts/upgrade b/scripts/upgrade
index 2190dc2..1e7e2e2 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -31,7 +31,7 @@ fi
 if [[ "$upgrade_from_opt" == "false" ]]; then
     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"
 fi
 
 #=================================================
@@ -62,31 +62,30 @@ if [[ "$upgrade_from_opt" == "true" ]]; then
     done
 
     install_dir=/var/www/$app
-    ynh_app_setting_set --app=$app --key=install_dir --value=$install_dir
+    ynh_app_setting_set --app="$app" --key=install_dir --value="$install_dir"
 
     db_name=ihatemoney
     db_user=$db_name
-    ynh_app_setting_set --app=$app --key=db_name --value=$db_name
+    ynh_app_setting_set --app="$app" --key=db_name --value="$db_name"
 fi
 
 # If secret_key doesn't exist, create it
 if [ -z "${secret_key:-}" ]; then
     secret_key=$(ynh_string_random --length=32)
-    ynh_app_setting_set --app=$app --key=secret_key --value=$secret_key
+    ynh_app_setting_set --app="$app" --key=secret_key --value="$secret_key"
 fi
 
 # If hashed_password doesn't exist, create it
 if [ -z "${hashed_password:-}" ]; then
     password=$(ynh_string_random --length=16)
     hashed_password=$(_hash_password "$password")
-    ynh_secure_remove --file="$install_dir/key.txt"
-    ynh_app_setting_set --app=$app --key=hashed_password --value=$hashed_password
+    ynh_app_setting_set --app="$app" --key=hashed_password --value="$hashed_password"
 fi
 
 if [ ! -d "/var/log/$app" ]; then
     # Configure log directory
     mkdir -p "/var/log/$app"
-    chown -R $app:$app "/var/log/$app"
+    chown -R "$app:$app" "/var/log/$app"
 fi
 
 
@@ -101,10 +100,6 @@ ynh_secure_remove --file="$install_dir/venv"
 __ynh_python_venv_setup --venv_dir="$install_dir/venv" --packages "${pip_dependencies[*]}"
 python_venv_site_packages=$(__ynh_python_venv_get_site_packages_dir -d "$install_dir/venv")
 
-chmod 750 "$install_dir"
-chmod -R o-rwx "$install_dir"
-chown -R $app:www-data "$install_dir"
-
 #=================================================
 # NGINX CONFIGURATION
 #=================================================
@@ -119,23 +114,20 @@ ynh_add_nginx_config
 #=================================================
 ynh_script_progression --message="Updating a configuration file..."
 
-ynh_add_config --template="../conf/gunicorn.conf.py" --destination="$install_dir/gunicorn.conf.py"
-chmod 640 "$install_dir/gunicorn.conf.py"
-chown $app:$app "$install_dir/gunicorn.conf.py"
-
 # Allows to comment some config lines if not using sub path
 sub_path_only="$(if [[ "$path" == "/" ]]; then echo '# ' ; else echo ''; fi)"
 
+ynh_add_config --template="../conf/gunicorn.conf.py" --destination="$install_dir/gunicorn.conf.py"
 ynh_add_config --template="../conf/ihatemoney.cfg" --destination="$install_dir/ihatemoney.cfg"
-chmod 640 "$install_dir/ihatemoney.cfg"
-chown $app:$app "$install_dir/ihatemoney.cfg"
+
+chmod -R o-rwx "$install_dir"
+chown -R "$app:$app" "$install_dir"
 
 #=================================================
 # SETUP SYSTEMD
 #=================================================
 ynh_script_progression --message="Upgrading systemd configuration..." --weight=1
 
-# Create a dedicated systemd config
 ynh_add_systemd_config
 
 #=================================================
@@ -145,14 +137,14 @@ ynh_add_systemd_config
 #=================================================
 ynh_script_progression --message="Integrating service in YunoHost..." --weight=1
 
-yunohost service add $app --description="$app daemon for IHateMoney" --log=systemd
+yunohost service add "$app" --description="$app daemon for IHateMoney" --log=systemd
 
 #=================================================
 # START SYSTEMD SERVICE
 #=================================================
 ynh_script_progression --message="Starting a systemd service..." --weight=1
 
-ynh_systemd_action --service_name=$app --action="start" --line_match="Listening at"
+ynh_systemd_action --service_name="$app" --action="start" --line_match="Listening at"
 wait_gunicorn_start
 
 #=================================================